Question

Suppose scores on a college entrance exam are normally distributed with a mean of 550 and a standard deviation of 100.

Find the score that marks the cut-off for the top 16% of the scores. Round to two decimal places.

Question 5 options:

	450.55
	649.45
	462.89
	508.34

Question 6 (1 point)

Suppose scores on a college entrance exam are normally distributed with a mean of 550 and a standard deviation of 100.

Find the cut-off scores that define the middle 60%. Round to two decimal places.

Question 6 options:

	465.84 and 634.16
	456.48 and 643.61
	575.33 and 634.16
	465.84 and 575.33

Question 7:

Suppose scores on a college entrance exam are normally distributed with a mean of 550 and a standard deviation of 100.

What is the probability that the sample mean score will be greater than 565, in a random sample of 100 entrance exams? Round to 4 decimal places

Question 7 options:

	0.5596
	0.4404
	0.9332
	0.0668

Question 8 (1 point)

The running time for videos submitted to YouTube in a given week is normally distributed with a mean of 390 seconds and a standard deviation of 148 seconds.

Suppose that a sample of 40 voters is selected. What is the probability that the mean running time for the sample exceeds six minutes? (Don't overlook: How many seconds are in 1 minute?)

Question 8 options:

	0.5803
	0.9001
	0.9953
	1

Question 9 (1 point)

On a certain television channel, 18% of commercials are local advertisers. A sample of 120 commercials is selected.

What is the probability that more than 20% of the commercials in the sample are local advertisers?

Question 9 options:

	0.0 or 1 x 10-59
	0.7081
	0.2844
	0.7158

Question 10 (1 point)

On a certain television channel, 18% of commercials are local advertisers. A sample of 120 commercials is selected.

Would it be unusual for more than 25% of the commercials in the sample are local advertisers?

Question 10 options:

	No
	Yes

Answer 1