Question

The police department of a major city needs to update its budget. For this​ purpose, they need to understand the variation in their fines collected from motorists for speeding. As a​ sample, they recorded the speeds of cars driving past a location with a 20 mph speed​ limit, a place that in the past has been known for producing fines. The mean of 100 representative readings was 23.65 ​mph, with a standard deviation of 3.61 mph. ​b) Which would be more​ unusual, a car traveling 34 mph or one going 11 ​mph? ​

b) Choose the correct answer below and fill in the answer​ box(es) to complete your choice.

A. The car traveling 34 mph is more unusual. It is ____ nothing standard deviations from the​ mean, while the car traveling 11 mph is nothing standard deviations from the mean. ​(Round to two decimal places as​ needed.

B. The car traveling 11 mph is more unusual. It is ____ nothing standard deviations from the​ mean, while the car traveling 34 mph is nothing standard deviations from the mean. ​(Round to two decimal places as​ needed.)

C. Both cars are equally unusual. Both cars are____ nothing standard deviations from the mean. ​(Round to two decimal places as​ needed.)

Answer 1

To find that wether the given data is usual or unusual we need to find the Z score corresponding as

Z at 34

and Z at 11

Since both are unusual so, the interpretation would be

B. The car traveling 11 mph is more unusual. It is 35.04 standard deviations below from the​ mean, while the car traveling 34 mph is 28.67 standard deviations above from the mean. ​(Round to two decimal places as​ needed.)