Question

The time required to finish a test in normally distributed with a mean of 40 minutes and a standard deviation of 8 minutes. What is the probability that a student chosen at random will finish the test in less than 32 minutes?

Answer 1

Do you know the empirical rule for the normal distribution?

Answer 2

no

Answer 3

The section of the rule that is relevant to this question is:
Approximately 68% of the data points lie within the range\[\pm \sigma\ of\ \mu\]
Therefore approximately 32% of the data points lie outside the above-mentioned data range.
16% of the data points will be below the above-mentioned range and 16% will be above the above-mentioned range.
Do you follow this?

Answer 4

yes

Answer 5

Do you see the answer now?

Answer 6

16%?

Answer 7

Or 0.16. Good work!

Answer 8

thank you!

Answer 9

You're welcome :)