Answer: the correct option is e
Explanation:
Since the The length of time needed to complete a certain test is normally distributed, we would apply the the formula for normal distribution which is expressed as
z = (x - u)/s
Where
x = The length of time needed to complete a certain test
u = mean time
s = standard deviation
From the information given,
u = 62 minutes
s = 8 minutes
We want to find the probability the probability that it will take less than 74 minutes to complete the test. It is expressed as
P(x lesser than or equal to 74)
For x = 74,
z = (74 - 62)/8 = 1.5
Looking at the normal distribution table, the corresponding value for the z score is 0.9332
P(x lesser than or equal to 74) = 0.9332