A Highway Patrol Officer is asked to measure how fast cars are travelling down a busy residential road for an entire week. It is thought that the speed limit of this road needs to be changed. The Patrol Officer find the speeds to be normally distributed with a mean of 48mph and a standard deviation of 5mph.
a) Draw the distribution and shade in the area that represents speeds greater than 45mph (Done). What proportion of cars are exceeding the speed limit of 45mph?(Need) Must show work and provide Zscore. (need)
b) Draw the distribution and shade in the are that represents the approximate 10% of car speeds (Done). The top 10% of cars are travelling greater than what speed?(Need)