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Suppose the scores on tests given to all Juniors in the high school district are normally distributed with a mean of 72 and a standard deviation of 8. Find the probability that a randomly chosen Junior how to score between 62 and 76. The probability is?

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Final answer:

To calculate the probability of a score between 62 and 76, convert the scores to Z-scores and use a Z-table or software to find the probability associated with each Z-score. Subtracting the smaller from the larger probability gives the required probability.

Step-by-step explanation:

To find the probability that a randomly chosen Junior will score between 62 and 76 on a test when the scores are normally distributed with a mean of 72 and a standard deviation of 8, we will use the properties of the normal distribution. To do this, we convert the scores into Z-scores, which tell us how many standard deviations away from the mean our scores are.

The formula for a Z-score is:

Z = (X - μ) / σ

Where X is the score, μ (mu) is the mean, and σ (sigma) is the standard deviation. So for the scores of 62 and 76, we calculate their Z-scores:

Z62 = (62 - 72) / 8 = -1.25
Z76 = (76 - 72) / 8 = 0.5

You would then use a Z-table or statistical software to find the probabilities for these Z-scores and subtract the smaller probability from the larger one to get the probability of a score falling between 62 and 76.

User Rohit Pareek
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