Download Math 150 Test 1 Review 1.- Find the mean and standard deviation of

Math 150
Test 1 Review
1.- Find the mean and standard deviation of the following grouped data.
Class limits — F—
0-5
5
6 - 11
4
12 - 17
3
18 - 23
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— MP—
—F · MP—
— F · MP2 —
2.- Find the outliers (if any) in the following data set:
5, 6, 7, 8, 8, 9, 12, 12, 16, 18, 22, 24, 28, 40
3.- Suppose that P (A) = 0.22,P (B) = 0.33, and P (A ∩ B) = 0.16 find
(a) P (A ∪ B)
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(b) P (A ∩ B)
(c) P (B ∩ A)
(d) P (A|B)
(e) P (B|A)
(g) Are A an B independent? Explain
4.- For the following data: 9,8,12,10,10,7,9,7,1,4,5,8,14
(a) Find the five number summary.
(b) Draw a box plot.
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(c) Find P33 .
(d) Find the mean, the median, and the mode.
5.- Solve the following probabilities.
High School
College
Republican
100
50
Democrat
70
80
Independent
30
70
(a) What is the probability that a randomly selected person is Republican?
(b) What is the probability that a randomly selected person is Republican or College Student?
(c) If the person selected was an Independent, what is the probability that it was a College Student?
(d) Are Republican and College independent events?
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6.- According to a local survey 55% of Angelinos pray every day. If you randomly select 4 Angelinos:
(a) what is the probability that all pray everyday?
(b) what is the probability that none of pray?
(c) what is the probability that at least one prays everyday?
7.- Suppose that 45% of the population is male and that 12% are smokers. If 8% of females are
smokers, what is the probability that
(a) A randomly selected person is a smoker?
(b) A randomly selected person is NOT a smoker?
(c) If the person selected was a smoker, that the person was male?
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8.- Mickey rats goes to Target and buys two alarm clocks. The probability that any of the alarms
will fail on any given day is 1%.
(a) What is the probability that both of them will work next Friday?
(b) What is the probability that both of them will fail next Friday?
(c) What is the probability that the alarms will wake him up next Friday?
(d) What is the percent increase in reliability by having two alarms as compared to one?
9.- The simple Passcode for an iPhone consists of four digits (which can be repeated).
(a) How many different simple Passcodes are there for any iPhone?
(b) If your boyfriend has an iPhone with a Passcode on it, what is the probability that you will
guess the correct Passcode in the first try?
(c) Your boyfriend has set the Passcode so that after three failed attempts the iPhone locks. What
is the probability of this happening?
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10. T/F section.
(a) s2 is always more than s.
(b) If A and B are independent then P (A ∩ B) = 0.
(c) The median and Q2 are the same.
(d) If A and B are mutually exclusive then P (A ∩ B) = 1
(e) If P (A) = 0.7, then P (A) = 12 .
(f) The median and the midrange could be the same.
(g) If A and B are independent then P (A|B) = P (B)
(h) For any two events P (A ∩ B) ≥ P (A).
(i) IQR = Q3 − 1.5Q1
(j) If A and B are independent then P (A ∪ B) = P (A) + P (B) − P (A)P (B)
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