Question

The mean length of time required to complete the Columbus Marathon was 4.5 hours. The standard deviation of the times was 0.50 hours. Assume that the racing times were approximately normally distributed. What is the probability that a randomly selected runner completed the race in less than 3.6 hours? Group of answer choices 0.9641 -1.8 0.4641 0.0359

Answer 1

Solution :

Given that ,

mean = = 4.5

standard deviation = = 0.50

P(x < 3.6) = P[(x - ) / < (3.6 - 4.5) / 0.50]

= P(z < -1.8)

= 0.0359

Probability = 0.0359