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What is normal?

What is normal?. Standard Normal Distribution The standard normal distribution is a special case of the normal distribution. It is the distribution

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What is normal?

Standard Normal Distribution

The standard normal distribution is a special case of the normal distribution. It is the distribution that occurs when a distribution has a mean of zero and a standard deviation of one.

The normal random variable of a standard normal distribution is called a standard score or a z-score. Every normal random variable X can be transformed into a z score via the following equation:

zx

Here’s a question –

Mandee took the ACT and received a score of 33, but Daniel (who is interested in East Coast Ivy League schools) took the SAT and received a score of 2230. Jessica got a 3 on the ACT and is obviously not part of the question…

Who has bragging rights?

ACT is normal, N(21.8,3.45)SAT is normal, N(1546, 291)

To find percentages in a normal distribution:

To find percentiles in a normal distribution…

Calculator functions: