Question

Question 11

A retailer finds that the demand for a very popular board game averages 100 per week with a standard deviation of 20. If the seller wishes to have adequate stock 90% of the time, how many of the games must she keep on hand?

	a.	139.2
	b.	125.6
	c.	132.9
	d.	100.0
	e.	195.0

Question 13

A new car salesperson knows that he sells cars to one customer out of 20 who enter the showroom. The probability that he will sell a car to exactly one of the next three customers is:

	a.	0.0075
	b.	0.9939
	c.	0.0851
	d.	0.0071
	e.	0.1354

A survey of college students taking pass to be certified as public school teachers shows that 85 percent pass. On a national exam day, 12,000 students take the test. Let x denote the number who pass. The mean and standard deviation of the random variable X are, respectively,:

	a.	10,200; 1530
	b.	1800; 39.11
	c.	1200; 35.71
	d.	10,200; 39.11
	e.	1800; 1530

Question 15

Using the standard normal table, the total area between z=0.00 and -1.38 is:

	a.	0.0494
	b.	0.4656
	c.	0.4162
	d.	0.1554
	e.	0.1005

Question 16

A salesman who uses his car extensivel;y finds that his gasoline bills average $125.32 per month with a standard deviation of $49.51. The probability that his bill will be more than $50 a month and less than $150 for a single month is:

	a.	0.6272
	b.	0.6915
	c.	0.4357
	d.	0.1915
	e.	0.3728

Given that z is a standard normal random variable and that the area to the right of z is 0.6950, then the value of z must be:

	a.	-0.51
	b.	0.51
	c.	0.86
	d.	-0.86

Answer 1