SOLUTION: 1. Assume that police response time to emergency calls is normally distributed with a mean of 9 minutes and a standard deviation of 2 minutes. Determine the percent of emergency ca

Algebra ->  Probability-and-statistics -> SOLUTION: 1. Assume that police response time to emergency calls is normally distributed with a mean of 9 minutes and a standard deviation of 2 minutes. Determine the percent of emergency ca      Log On


   

Question 820938: 1. Assume that police response time to emergency calls is normally distributed with a mean of 9 minutes and a standard deviation of 2 minutes. Determine the percent of emergency calls with a police response time less than 12.2 minutes. Round to the nearest hundredth.

2. Assume that police response time to emergency calls is normally distributed with a mean of 9 minutes and a standard deviation of 2 minutes. Determine the percent of emergency calls with a police response time more than 7.8 minutes. Round to the nearest hundredth.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

 1. z = (12.2-9)/2 = 3.2/2 = 1.6

  P(x <12.2min) = P(z< 1.6) = 94.52%

2. z = (7.8-9)/2 = -1.2/2 = -.6

 P(x >7.8min) = P(z > .6) = 72.57%