Question

Suppose that it is reported in the news that 12% of the people living and working in Kokomo feel that their commute is too long. What is the travel time to work that separates the top 12% of people with the longest travel times and the lower 88%

Answer 1

22.3 minutes

Explanation:

The computation of the travel time is as follows:

Given that

`\mu` = 17

And, the standard deviation is 4.5

P(X≤C) = 0.88

P( x -
`\mu`) ÷
`\sigma` ≤ (C -
`\mu`) ÷
`\sigma` = 0.88

(C -
`\mu`) ÷
`\sigma` = 1.175

c =
`\mu` + 1.175 ×
`\sigma`

= 17 + 1.175 × 4.5

= 22.3 minutes

Hence, the travel time is 22.3 minutes