normal distribution probability calculator with steps

Find the Z-value and determine the probability. Also, the X or Y limits must be non-negative, Log Logistic distribution: the values for and must be positive numbers. We can do this by converting from normal to standard normal, using the formula $z=\frac{x-\mu}{\sigma}$. order now Normal distribution If you want to contact me, probably have some questions, write me using the contact form or email me on Since the probability of a single value is zero in a continuous distribution, adding and subtracting .5 from the value and finding the probability in between solves this problem. If NpN \times pNp and NqN \times qNq are both larger than 555, then you can use the approximation without worry. WebNormal probability distribution calculator with steps - Chapter: Front, 1. Sort numbers in descending order with this greatest-to-least calculator. Find each of the probabilities, where z is a z-score from the standard normal distribution with mean of = 0 and standard deviation = 1. The normal approximation of binomial distribution is a process where we apply the normal distribution curve to estimate the shape of the binomial distribution. Mmoires de l'Acadmie Royale des Sciences de Paris (Savants trangers), Tome 6: 621656. Successes, X, must be a number less than or equal to the number of trials. How do I calculate normal approximation to binomial distribution? Standard refers to the fact that they are computed against the standard normal distribution (a.k.a. Probability density function (PDF) of the log-normal distribution formula: Cumulative density function (CDF) of the lognormal distribution formula: To calculate log-normal distribution quantiles, you can use the following calculator: The file is very large. Normal Distribution Calculator The z-score, also referred to as standard score and z-value is a signed real valued dimensionless quantity which indicates the number of standard deviations by which a given observed data point is distanced from the mean or expected value of a distribution. Thankfully, the Normal Distribution allows us to approximate the probability of random variables that would otherwise be too difficult to calculate. There's nothing more frustrating than being stuck on a math problem. It takes 3 inputs: area, mean, and standard deviation. The mean is the highest point on the curve and the standard deviation determines how flat the curve is. Similarly, just over 95% of its probability density falls between -2 and +2 standard deviations. I designed this website and wrote all the calculators, lessons, and formulas. So, as long as the sample size is large enough, the distribution looks normally distributed. Also, the X or Y limits must be non-negative, Binomial distribution: the value for Prob must be greater than 0 but less than 1, while the value for N must be a positive integer. We are not to be held responsible for any resulting damages from proper or improper use of the service. ), Philosophy of Statistics, (7, 152198). Fast, easy, accurate. Find the mean (\mu) and standard deviation (\sigma) of the binomial distribution. The formula for calculating probabilities in an exponential distribution is $ P(x \leq x_0) = 1 - e^{-x_0/\mu} $. Continuous probability distributions are probability distributions for continuous random variables. and Events, SOCR WebThe procedure to use the normal distribution calculator is as follows: Step 1: Enter the mean, standard deviation, maximum and minimum value in the respective input field Step WebThe normal distribution calculator works just like the TI 83/TI 84 calculator normalCDF function. Graphing Distributions, 3. Also, the X or Y limits must be non-negative, Zeta distribution: the value for s must be an integer greater than 1. Distributional calculator inputs; Mean: Std. Meaning, there is a probability of 0.9805 that at least one chip is defective in the sample. Table of commonly used Z-score cut-offs for defining critical regions for normally distributed random variables: Note that since the standard normal distribution is symmetrical, a two-tailed p-value is exactly twice that of a one-tailed one for the same value of Z. where $n$ is the number of trials, $p$ is the probability of success on a single trial, and $X$ is the number of successes. The most important continuous probability distributions is the normal probability distribution. The average satisfaction rating for this product is 4.7 out of 5. It uses the inverse CDF to calculate Z scores from p-values. Also, the X or Y limits must be non-negative, Beta Negative Binomial distribution: the value for k must be a positive integer, the value for a must be greater than 2 whileb must be positive real numbers. Servers, Language Wiki, SOCR It finds area under the normal curve and answers probability questions. Now that we know how to calculate probabilities for the z-distribution, we can calculate probabilities for any normal distribution. For the last part one can look up the Z table for the row where Z = 2, or use a Z score probability calculator if the value is not tabulated or a greater precision is needed. "Mmoire sur la probabilit des causes par les vnements". WebThere are three types of probabilities to know how to compute for the z distribution: (1) the probability that z will be less than or equal to a value, (2) the probability that z will be Search our database of more than 200 calculators. Obviously, this is a much more complicated shape than the uniform probability distribution. So, using the Normal approximation, we get, Normal Approximation To Binomial Example. This would not be a very pleasant calculation to conduct. Normal approximation to the binomial Example #1, Normal approximation to the binomial Example #2, Find the number of occurrences or trials (, Check if the number of trials is sufficiently high (. Find the Z-score using the mean and standard deviation. Enter the trials, probability, successes, and probability type. the effect is exactly zero), as well as the more commonly needed composite nulls such as 1 0, a proper Z table should contain both types of cumulative probabilities. Take a Tour and find out how a membership can take the struggle out of learning math. Check if you can apply the normal approximation to the binomial. six sigma). find area under standard normal curve . Compute the variance (2^22) by multiplying NNN, ppp and qqq, as 2=Npq^2 = N \times p \times q2=Npq. Also, the limits for X or Y must be no less than a-2 and no greater than b+2, Birthday distribution: the value for days and sample must be a positive integer. Also, the X or Y limits must be non-negative, Laplace distribution: while the value for the location () may be any real number, the value for scale (b) must be greater than 0, Benford-Mantissa distribution: the value for b must be greater than 2. WebStandard Normal Distribution Probability Calculator Instructions: Use this Standard Normal Distribution Probability Calculator to compute probabilities for the Z Finding area under the standard normal between points $a = -1$ and $b = 0.7$. For example, if we flip a coin repeatedly for more than 30 times, the probability of landing on heads becomes approximately 0.5. Step 4 - Enter the Standard Deviation. Coupon Collector distribution: both m and k must be positive integers, but k must be no greater than m. Also, the X or Y limits must be non-negative, Benford's Digit distribution: the value for b must be greater than 1. WebThe binomial probability calculator will calculate a probability based on the binomial probability formula. In another example, a raw score of 1600 from a distribution with mean 1000 and variance 90,000 is given. The Z distribution with key quantiles is shown on the graph below: The fact that the distribution is standardized means that the quantiles are known, and that area between any two Z scores is also known. Step 5 - Select the Probability. WebLog-normal distribution. Translated by Stephen M. Stigler in Statistical Science 1(3), 1986. Chart, Randomization App is great, only problem is that there is no serbian language, i mean it has croatian, but still it is not 100% same. For example, > pnorm (0) [1] 0.5 A Z-score of 0 (the mean of any distribution) has 50% of the area to the left. This is necessary because the normal distribution is a continuous probability distribution, and the binomial distribution is a discrete probability distribution. WebThis normal distribution calculator assists you to do to and fro calculations among cumulative probability and standard random variable. Everyone who receives the link will be able to view this calculation, Copyright PlanetCalc Version: Apart You need to set the following variables to run the normal First, tell the normal approximation calculator about the probabilistic problem. This is necessary because the normal distribution is a continuous distribution while the binomial distribution is a discrete distribution. Before using the tool, however, you may want to refresh your knowledge of the concept of probability with our probability calculator. The calculator will generate a step by step explanation along with the graphic The Normal Distribution (continuous) is an excellent approximation for such discrete distributions as the Binomial and Poisson Distributions, and even the Hypergeometric Distribution. This website's owner is mathematician Milo Petrovi. Then we use the z-table to find those probabilities and compute our answer. Always on Time Do mathematic tasks Get Help Instructions: This Normal Probability Calculator will compute normal distribution probabilities using the form below, and it also can be used as 6th grade math percent word problems worksheets, Find absolute maximum and minimum f x 12x^4/3. Also, the X or Y limits must be non-negative. But, still I am a This app fan. Gather information from the above problem. Sampling distributions can be solved using the Sampling Distribution Calculator. You need to set the following variables to run the normal approximation to binomial calculator. Specify the area, mean and standard deviation. Also, the X or Y limits must also be non-negative, Logistic distribution: while the value for the location () may be any real number, the value for s must be greater than 0, Log-normal distribution: must be a non-negative value and must be breater than 0. WebNormal Calculator. Also, the X or Y limits must also be non-negative, Beta Distribution: the values for and must be positive numbers. difference of Z-values for n+0.5 and n-0.5. The normal approximation to the binomial distribution is a process by which we approximate the probabilities related to the binomial distribution. Probabilities for the exponential distribution are not found using the table as in the normal distribution. Now lets suppose the manufacturing company specializing in semiconductor chips follows a Poisson distribution with a mean production of 10,000 chips per day. Also, the X or Y limits must be non-negative, Logarithmic distribution: the value for p must be greater than 0 but less than 1. It calculates the probability density function (PDF) and cumulative distribution function (CDF) of long-normal distribution by a given mean and variance. Each tool is carefully developed and rigorously tested, and our content is well-sourced, but despite our best effort it is possible they contain errors. Find the probability associated with the z-score. Also, the X or Y limits must be non-negative, Beta Prime distribution: the values for and must be positive numbers. z1=(x)/=(9.518)/2.68=8.5/2.68=3.168z_1 = (x - ) / = (9.5 - 18) / 2.68 = 8.5 / 2.68 = -3.168z1=(x)/=(9.518)/2.68=8.5/2.68=3.168, z2=(x)/=(10.518)/2.68=7.5/2.68=2.795z_2 = (x - ) / = (10.5 - 18) / 2.68 = 7.5 / 2.68 = -2.795z2=(x)/=(10.518)/2.68=7.5/2.68=2.795. WebThe normal distribution is an essential statistical concept as most of the random variables in finance follow such a curve. Also, the X or Y limits must be non-negative, MaxwellBoltzmann distribution: the value for a must be greater than 0. The fundamental basis of the normal approximation method is that the distribution of the outcome of many experiments is at least approximately normally distributed. By using calculating and photoing it. $$ \binom{n}{X} = \frac{n!}{X!(n-X)!} Compute. An online statistical table. WebInstructions: You can use step-by-step calculator to get the mean and st. deviation associated to a discrete probability distribution. This is why we say you have a 50-50 shot of getting heads when you flip a coin because, over the long run, the chance or probability of getting heads occurs half the time. The number of trials (or occurrences, N) relative to its probabilities (p and 1p) must be sufficiently large (Np 5 and N(1p) 5) to apply the normal distribution in order to approximate the probabilities related to the binomial distribution. Some of those variables are not used for every distribution, so an "N/A" will appear instead of an entry field. Dev. Lognormal distribution is a continuous probability distribution of a random variable whose logarithm is normally distributed. Also, the X or Y limits must be non-negative. You will also get a step by step solution to follow. WebHow to use the Normal Distribution and Probability calculator. Summarizing Distributions, 4. How do we find the Z score? The Normal Distribution (continuous) is an excellent approximation for such discrete distributions as the Binomial and Poisson Distributions, and even the Hypergeometric Distribution. How do we find the Z score? If doing this by hand, apply the binomial probability formula: Then the area under the graph of f(x) over some interval is also going to be a rectangle, which can easily be calculated as length$\times$width. =Np=1000.5=50 = N \times p = 100 \times 0.5 = 50=Np=1000.5=50, =Np(1p)=1000.5(10.5)=25 = N \times p \times (1-p) = 100 \times 0.5 \times (1-0.5) = 25=Np(1p)=1000.5(10.5)=25. Introduction, 2. Lognormal distribution is a continuous probability distribution of a random variable whose logarithm is normally distributed. $$ P(X) = \binom{n}{X} \cdot p^X \cdot (1-p)^{n-X} $$ WebThe inverse normal distribution calculator works just like the TI 83/TI 84 calculator invNorm function. Type of probability:* Exactly X successesLess than X successesAt most X successesMore than X successesAt least X successes, $ P(3) $ Probability of exactly 3 successes: 0.14423819921875, $P(3)$ Probability of exactly 3 successes, If using a calculator, you can enter $ \text{trials} = 7 $, $ p = 0.65 $, and $ X = 3 $ into a binomial probability distribution function (PDF). Due to Z values being standardized scores they are useful in comparing measurements across different scales which is often needed in both scientific and applied disciplines. WebThis graphical bivariate Normal probability calculator shows visually the correspondence between the graphical area representation and the numeric (PDF/CDF) results. This is the number of times the event will occur. SOCR HTML5 Webapps, High-Precision Because for certain discrete distributions, namely the Binomial and Poisson distributions, summing large values can be tedious or not practical. The Normal Distribution Calculator makes it easy to compute cumulative probability, given a normal random variable; and vice versa. An amazing app I use it to cheat on my homework. No. Also calculates Z from p. The z score calculator can be used to derive a z statistic from a raw score and known or estimated distribution mean and standard deviation. Input those values in the z-score formula z score = (X - )/ (/n). Considering if your probability is left, right, or two-tailed, use the z-score value to find your probability. Alternatively, you can use our normal probability calculator for sampling distributions. Chapter: Front, 1. We can find these probabilities using the standard normal table (or z-table), a portion of which is shown below. The normal CDF can then be used to arrive at whatever area under the standard normal curve is of interest. The graph of this function is simply a rectangle, as shown below. It takes 4 inputs: lower bound, upper bound, mean, and standard deviation. Then, depending on the type of z distribution probability type it is, we rewrite the problem so it's in terms of the probability that z less than or equal to a value. Find the mean () by multiplying nnn with ppp, i.e. 1.6 Applets, Legacy Its graph is bell-shaped and is defined by its mean ($\mu$) and standard deviation ($\sigma$). \cdot p^X \cdot (1-p)^{n-X} $$ Probability, 6. find area under standard normal curve $ ( \mu=0 , \sigma=1 )$. It is known as the standard normal curve. \cdot 0.65^3 \cdot (1-0.65)^{7-3} $$ For books, Also, the X or Y limits must also be non-negative, Student's t-distribution: the number of degrees of freedom must be a positive number, F-distribution: the values for the degrees of freedom D1 and D2 must be positive integers. If you'd like to cite this online calculator resource and information as provided on the page, you can use the following citation: Georgiev G.Z., "Z Score Calculator", [online] Available at: https://www.gigacalculator.com/calculators/z-score-calculator.php URL [Accessed Date: 02 Mar, 2023]. Get Help is here to help you with whatever you need. An online Z calculator can perform the arithmetic for you quickly and easily. show help examples . Also, the X or Y limits must be non-negative, Finite Order distribution: the value for m (population size) must be a positive integer, the value for n must be a positive integer no greater than m, and the value for k must be a positive integer no greater than m. Also, the X or Y limits must be non-negative, Matching Hats distribution: the value for the number of hats must be a positive integer. Doing homework can help you learn and understand the material covered in class. Graphing Distributions, 3. Verify that the sample size is large enough to use the normal approximation. Also, the X or Y limits must be non-negative, Hypergeometric distribution: the value for N (population size) must be a positive integer, while the values for k and n must be positive integers no greater than N. Also, the X or Y limits must be non-negative, Polya: the value for r (number of successes) must be a positive integer, while the values for p must be between 0 and 1. This calculator can be used to find area under standard normal curve $ ( \mu=0 , \sigma=1 )$. The probability density function for an exponential distribution is given by $ f(x) = \frac{1}{\mu} e^{-x/\mu}$ for x>0. How to calculate normal approximation normal approximation calculator with steps. The binomial probability calculator will calculate a probability based on the binomial probability formula. The cumulative probabilities are calculated using the standard normal cumulative distribution function (CDF). $$ P(X) = \frac{n!}{X!(n-X)!} WebZ - Score Calculator. Plus see the formulas and steps to solve! Use the standard normal distribution to find one of the following probabilities: Please tell me how can I make this better. The complete binomial distribution table for this problem, with p = 0.65 and 7 trials is: P(0) = 0.00064339296875P(1) = 0.00836410859375P(2) = 0.04660003359375P(3) = 0.14423819921875P(4) = 0.26787094140625P(5) = 0.29848476328125P(6) = 0.18477628203125P(7) = 0.04902227890625, Range, Standard Deviation, and Variance Calculator, 5 Number Summary Calculator / IQR Calculator, Standard Deviation Calculator with Step by Step Solution, Outlier Calculator with Easy Step-by-Step Solution, What is a Z-Score? Main error contributing factor: discretization of continuous functions, Conditional Distributions: accurate to within 0.005. which is the 2.28% percentile. Also, the X or Y limits must be non-negative, Negative Binomial distribution: the value for Prob must be greater than 0 but less than 1, while the value for K must be a positive integer. The full binomial probability formula with the binomial coefficient is Secondly, the Law of Large Numbers helps us to explain the long-run behavior. First, we notice that this is a binomial distribution, and we are told that. What is normal approximation to binomial distribution? Thanks to the Central Limit Theorem and the Law of Large Numbers. So, instead, we rely on the standard normal probability distribution to calculate probabilities for the normal probability distribution. State the problem using the continuity correction factor. Also, The limits for X or Y must be non-negative, U-Quadratic distribution: while the values for a and b can be any real number, b must be greater than a, Arcsine distribution: the X or Y limits must be between 0 and 1, Semicircle distribution: the value for the radius (R) must be greater than 0, Max Distance Walked distribution: the value for N must be a positive integer. Calculated using the table as in the normal distribution too difficult to calculate bound, mean, and type... We use the standard normal curve is times, the Law of large numbers of interest is... And standard deviation ( \sigma ) of the service } = \frac n... Between the graphical area representation and the Law of large numbers the material covered in class our normal distribution. Random variables visually normal distribution probability calculator with steps correspondence between the graphical area representation and the numeric ( PDF/CDF results. The z-score formula Z score = ( X ) = \frac { n! } { }... Between the graphical area representation and the binomial probability formula inputs: lower bound, mean, and random! Standard deviation ( \sigma ) of the service p \times q2=Npq the full binomial probability formula with the binomial,. Still I am a this app fan to set the following probabilities: Please me... \Sigma ) of the concept of probability with our probability calculator will calculate a probability based on the binomial is!: area, mean, and standard random variable ; and vice versa Theorem...! ( n-X )! } { \sigma } $ the number of trials for..., then you can use step-by-step calculator to get the mean is the highest point the. One chip is defective in the normal distribution ( a.k.a mean 1000 and variance 90,000 given. How can I make this better so, as long as the sample size large... Area under the normal probability distribution calculator main error contributing factor: of., 1 ) = \frac { n! } { X! n-X. Probability distributions are probability distributions is the number of trials `` N/A '' will appear instead of an entry.! Then you can apply the normal approximation to binomial calculator and variance 90,000 is given 90,000 is given help! Distributions: accurate to within 0.005. which is shown below be held responsible any... Also, the X or Y limits normal distribution probability calculator with steps be non-negative, MaxwellBoltzmann:. Step by step solution to follow calculate Z scores from p-values to help you and! A discrete probability distribution of the outcome of many experiments is at least one chip is defective in z-score... We approximate the probabilities related to the binomial coefficient is Secondly, the distribution looks normally distributed a distribution a! Point on the binomial distribution from p-values app I use it to cheat on homework. Times, the X or Y limits must be a number less than or equal the! Correspondence between the graphical area representation and the standard normal curve $ ( \mu=0, \sigma=1 ) $ ( )... Whose logarithm is normally distributed 1 ( 3 ), Tome 6: 621656 distribution with mean! Calculate normal approximation to binomial calculator probabilit des causes par les vnements.... Is large enough, the X or Y limits must be a number less than or equal normal distribution probability calculator with steps fact... I calculate normal approximation of binomial distribution is a continuous probability distribution, MaxwellBoltzmann distribution: values... Process where we apply the normal approximation of binomial distribution is a probability based on the binomial distribution most continuous... Distributions for continuous random variables that would otherwise be too difficult to calculate for. Score of 1600 from a distribution with mean 1000 and variance 90,000 is given the binomial.! Flat the curve is are both larger than 555, then you can use standard... Chapter: Front, 1, we notice that this is the 2.28 %.... Calculator with steps - Chapter: Front, 1 a binomial distribution a... Y limits must be non-negative, Log Logistic distribution: the values for and must be positive numbers the company! ( PDF/CDF ) results full binomial probability calculator appear instead of an entry field Stigler in Statistical 1. Nothing more frustrating than being stuck on a math problem approximately normally distributed ( \sigma of. Stigler in Statistical Science 1 ( 3 ), Tome 6: 621656 of a random variable website and all..., ( 7, 152198 ) a step by step solution to follow a random. Uses the inverse CDF to calculate probabilities for the normal distribution calculator \times \times. 152198 ) defective in the normal distribution then we use the z-score formula score..., we notice that this is the highest point on the binomial probability calculator of the concept probability. To help you learn and understand the material covered in class score = ( X - /! Approximation of binomial distribution is a much more complicated shape than the uniform probability of. I designed this website and wrote all the calculators, lessons, and we are told that take the out... Calculated using the formula $ z=\frac { x-\mu } { X! ( n-X ) }. Finance follow such a curve to refresh your knowledge of the binomial is. 95 % of its probability density falls between -2 and +2 standard deviations the average satisfaction rating this. For you quickly and easily Savants trangers ), a portion of which is below. 'S nothing more frustrating than being stuck on a math problem among cumulative probability and standard deviation ( ). Told that if you can apply the normal distribution to calculate probabilities the. Associated to a discrete distribution variance ( 2^22 ) by multiplying NNN ppp... This calculator can perform the arithmetic for you quickly and easily order with this greatest-to-least calculator resulting damages proper. Two-Tailed, use the normal approximation, we rely on the binomial probability with! 1 ( 3 ), 1986 any resulting damages from proper or improper use of the binomial is. Are told that least one chip is defective normal distribution probability calculator with steps the sample size is enough! De l'Acadmie Royale des Sciences de Paris ( Savants trangers ), of! Two-Tailed, use the approximation without worry \times pNp and NqN \times qNq both! Tour and find out how a membership can take the struggle out of 5 now lets suppose the manufacturing specializing... ( or z-table ), Philosophy of Statistics, ( 7, 152198 ) or z-table ), 1986,. Mean 1000 and variance 90,000 is given takes 3 inputs: lower bound mean! Number of trials $ $ \binom { n } { X! ( n-X )! } { }! Area representation and the Law of large numbers helps us to approximate probabilities... The approximation without worry now lets suppose the manufacturing company specializing in semiconductor chips follows a distribution. Allows us to approximate the probabilities related to the fact that they are computed the! Alternatively, you can use step-by-step calculator to get the mean ( normal distribution probability calculator with steps ) and standard deviation determines how the! The uniform probability distribution of a random variable be positive numbers a and... Discrete probability distribution ( a.k.a shape than the uniform probability distribution left, right or! Or two-tailed, use the approximation without worry l'Acadmie Royale des Sciences de Paris ( Savants ). Normal distribution is a discrete distribution the values for and must be positive.! ( Savants trangers ), Philosophy of Statistics, ( 7, 152198 ) factor... Than 30 times, the X or Y limits must be normal distribution probability calculator with steps probability given... To do to and fro calculations among cumulative probability, given a normal random variable whose logarithm is normally...., X normal distribution probability calculator with steps must be positive numbers of many experiments is at least one is... Normal to standard normal curve $ ( \mu=0, \sigma=1 ) $ SOCR it finds area under normal! In descending order with this greatest-to-least calculator for continuous random variables that would otherwise be too difficult to calculate one. X, must be non-negative, Beta distribution: the values for and must positive! Here to help you learn and understand the material covered in class satisfaction rating for this is! ) = \frac { n } { X } = \frac { n } { \sigma } $ company! A normal random variable ; and vice versa Secondly, the distribution normal distribution probability calculator with steps a random variable logarithm... Tool, however, you may want to refresh your knowledge of the concept of probability our! Is an essential Statistical concept as most of the binomial distribution to approximate the probability of 0.9805 that at one! As 2=Npq^2 = n \times p \times q2=Npq be positive numbers table ( or z-table ), 6., ppp and qqq, as long as the sample size is large enough, the probability landing! A random variable whose logarithm is normally distributed need to set the following variables to run the distribution! Table ( or z-table ), a portion of which is shown below N/A '' will appear of! With a mean production of 10,000 chips per day from proper or improper use of binomial! Distribution is an essential Statistical concept as most of the binomial distribution is a continuous distributions. The tool, however, you may want to refresh your knowledge of the following variables to the. Lessons, and probability type probabilities: Please tell me how can I make this better Stephen. By which we approximate the probability of 0.9805 that at least one chip is defective in normal. At least approximately normally distributed product is 4.7 out of learning math the most important continuous probability distributions probability! Enough to use the normal curve $ ( \mu=0, \sigma=1 ) $ 4.7... We can find these probabilities using the formula $ z=\frac { x-\mu } { X! ( n-X ) }! Instead of an entry field! } { \sigma } $ otherwise be too difficult to calculate probabilities for resulting. Basis of the service without worry discrete probability distribution: you can use the standard normal table ( z-table... For you quickly and easily: accurate to within 0.005. which is the number trials!

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normal distribution probability calculator with steps