Question

QUESTION 17

MC1703: A test consists of 10 multiple choice questions, each with four possible answers, one of which is correct. To pass, a student must get at least 5 correct on the test. If a student randomly guesses at every question, what is the probability that the student fails the test?

	a.	1.6%
	b.	5.8%
	c.	75%
	d.	92.2%
	e.	98.0%
	f.	None of these

1 points   

QUESTION 18

MC1802: Each child born to a particular set of parents has probability 0.25 of having blood type O. If these parents have 5 children, what is the probability that at most 2 of them have type O blood?

	a.	10.4%
	b.	26.4%
	c.	36.7%
	d.	63.3%
	e.	65.9%
	f.	89.6%

1 points   

QUESTION 19

MC1901: Corinne is a basketball player who makes 75% of her free throws over the course of a season. If she shoots 12 free throws in a game, what is the probability that she makes less than 7 of them?

	a.	5.4%
	b.	10.3%
	c.	15.8%
	d.	84.2%
	e.	89.7%
	f.	94.6%

1 points   

QUESTION 20

MC2005: You operate a restaurant. You read that a sample survey by the National Restaurant Association shows that 40% of adults are committed to eating nutritious food when eating out. 12 adult customers come to the restauarant. What is the probability that at least 5 of them are committed to eating nutritious food? Assume that the conditions for the binomial distribution are met.

	a.	22.7%
	b.	33.5%
	c.	43.8%
	d.	56.2%
	e.	66.5%
	f.	77.3%

1 points   

QUESTION 21

MC2102: What is true about the normal distribution?

I: It is a discrete distribution

II: It is a continuous distribution

III: It may be symmetric or skewed.

	a.	I only
	b.	II only
	c.	III only
	d.	I and II only
	e.	I and III only
	f.	II and III only
	g.	I, II, and III
	h.	None of these

1 points   

QUESTION 22

MC2204: Which of the following are true about z-scores?

I: They are positive whenever X is less than the mean in a normal distribution.

II: The standard normal distribution, which is the distribution of all z-scores, has a mean of 0 and standard deviation of 1.

III: They can be found by taking X, dividing by the standard deviation, and then subtracting the mean from the result.

	a.	I only
	b.	II only
	c.	III only
	d.	I and II only
	e.	I and III only
	f.	II and III only
	g.	I, II, and III
	h.	None of these

Answer 1

QUESTION 17

Sol: option d. 92.2%
Binomial Problem with n = 10 and p = 1/4 = 0.25
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5 correct on the test
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Solve using a TI-84 calculator:
P(X >= 5) = P(5<= x <=10) = P(X = 5, 6, 7, 8, 9, 10)
= P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8) + P(X = 9) + P(X = 10)
= 0.0584+ 0.0162+ 0.0031+ 0.0004+ 0+ 0
= 0.0781 or 92.2 %

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QUESTION 18

Sol:
f. 89.6%
Binomial Problem with n = 5 and p = 0.25
P(X<= 2) = 1-P(X = 2)
= 0.8964 or 89.6%