The average age of students in a career college is 28 years with a standard deviation of 12...
Question:
The average age of students in a career college is 28 years with a standard deviation of 12 years. It is known that the age of the students follows a normal distribution.
1. What is the probability that a randomly selected student is older than 32 years?
2. 25% of the students are older than how many years?
Gaussian Distribution:
Commonly known as the standard normal distribution, the Gaussian distribution gives a cumulative probability, raw scores take in a continuous distribution. The probability can be found by using a calculator, software, or the standard normal table.
Answer and Explanation: 1
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Let age in years of students in a career college be denoted by X:
{eq}X\sim N(28, 12) {/eq}
Using the standard normal table:
{eq}\begin{align*...
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Using the Normal Distribution: Practice Problems
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Using the normal distribution is a method for answering questions about large populations. Learn about using the normal distribution and finding the Z-score, and study one- and two-sided practice problems.
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