Question

Commute Time to Work The average commute to work (one way) is 25 minutes according to the 2005 American Community Survey. If we assume thatcommuting times are normally distributed and that the standard deviation is 6.1 minutes, find the probabilities. (b) The selected commuter spends less than 11 minutes commuting one way.P (x<11) =

Answer 1

mean: 25 minutes

standard deviation: 6.1 minutes

A 11 minutes commute time is 2.30 standard deviations away from the mean. In this case, we have, for a normal distribution:

`P(x<11)=P(x<\mu-2.3\sigma)=0.0107`