Question

A) Suppose that the mean and standard deviation of the scores on a statistics exam are 89.2 and 6.49, respectively, and are approximately normally distributed. Calculate the proportion of scores below 77.

	1) 0.0301
	2) 0.9699
	3) We do not have enough information to calculate the value.
	4) 0.2146
	5) 0.7854

B)

When students use the bus from their dorms, they have an average commute time of 8.974 minutes with standard deviation 3.1959 minutes. Approximately 66.9% of students reported a commute time less than how many minutes? Assume the distribution is approximately normal.

	1) 4.51
	2) 10.37
	3) 13.44
	4) We do not have enough information to calculate the value.
	5) 7.58

C)

The revenue of 200 companies is plotted and found to follow a bell curve. The mean is $637.485 million with a standard deviation of $27.6736 million. Would it be unusual for a randomly selected company to have a revenue above $687.08 million?

	1) The value is unusual.
	2) We do not have enough information to determine if the value is unusual.
	3) The value is not unusual.
	4) It is impossible for this value to occur with this distribution of data.
	5) The value is borderline unusual.

Answer 1