Question

Suppose that the duration of a particular type of criminal trial is known to be normally distributed with a mean of 22 days and a standard deviation of 6 days. 64% of all of these types of trials are completed within how many days

Answer 1

30 days

Explanation:

Look at you z-score table to find the value closest to .6400 (64%)

my table shows this corresponds to z-score + .36 standard deviation ABOVE the mean of 22 days

.36 * 22 = ~ 8 days

added to the mean 8 + 22 = 30 days