Answer to Question #191105 in Civil and Environmental Engineering for Joshua

Question

A civil engineer takes a public ride going to his firm. The average time for this trip is 24 minutes, with a standard deviation of 3.80 minutes. Find the probability that 2 of the next 3 trips will take at least 1/2 hour.

Answer 1

let's find the probability that a trip will take at least 1/2 hour

$P(X\ge30)=1-P (X<30)$

$=1-P(\frac{X-\mu}{\sigma}<\frac{30-24}{3.8})$

$=1-P(Z<1.58)$

$=1-0.9429$

$=0.0571$