# statistics

The GPAs of all students enrolled at a large university have an approximately normal distribution with a mean of 3.02 and a standard deviation of .29. Find the probability that the mean GPA of a random sample of 20 students selected from this university is

2.87 or lower

1. 👍 2
2. 👎 1
3. 👁 2,162
1. Find z-score:

z = (2.87 - 3.02)/(.29/√20) = ?

Calculate.

Check a z-table for the probability using the z-score. (Remember that the question is asking for "2.87 or lower" when looking at the table.)

1. 👍 0
2. 👎 0
2. 1.103

1. 👍 0
2. 👎 0

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