Solve the problem.
-A physical fitness association is including the mile run in its secondary-school fitness test. The time for this event for boys in secondary school is known to possess a normal distribution with a mean of 440 seconds and a
Standard deviation of 60 seconds. Between what times do we expect most (approximately 95%) of the boys to
Run the mile?
A) between 0 and 538.736 sec
B) between 322.4 and 557.6 sec
C) between 345 and 535 sec
D) between 341.3 and 538.736 sec

Question

Quizplus · Accepted Answer

For a normal distribution, approximately 95% of the data falls within 2 standard deviations of the mean. The mean is 440 seconds and the standard deviation is 60 seconds. Calculating 2 standard deviations from the mean gives us: 440 - 2(60) = 320 and 440 + 2(60) = 560. Therefore, most boys will run the mile between 320 and 560 seconds. Option B, 322.4 and 557.6 seconds, is the closest to this range.

Solve the Problem. -A Physical Fitness Association Is Including the Mile Run in Mile