Algebra 2
Review Chapter #12
Name ________________________________
Suppose you select a number at random from the sample space {5, 6, 7, 8, 9, 10, 11, 12, 13, 14}. Find each probability.
1. P(less than 7)
2. P(multiple of 3)
3. P(odd or prime)
4. A football player has made 27 out of 32 field goals. What is the Experimental probability he will make the next field goal?
A spinner is spun. State whether the events are mutually exclusive. Then find P(A or B).
5.
A = an odd number
B = a number  6
6.
A = an odd number
B = an even number
7.
Suppose you have a CD which contains a compilation of songs. Seven songs can be classified as rock, and three as blues.
Today you hit the shuffle button on your CD player, which plays the songs in a random order. Tomorrow you do the same
thing. What is the probability that the CD player plays a blues song first each day?
Use the results of the survey below to find each conditional probability.
How many radios do you have in your home?
8.
0 radios
1 radio
2 radios
3+ radios
Male respondents
1
5
16
10
Female respondents
1
9
13
12
P(male | 2 radios)
9.
P(2 radios | male)
10.
P(0 radios | female)
Use the following set of values for Exercises 11-13.
Round to the nearest hundredth.
98 99 99 103 101 102 104 89 87 90 90
11.
Find the mean, median, and mode(s) of the data set.
12.
Draw a box-and-whisker plot.
13.
Find the range.
16.
Find the 30th and 80th percentiles.
14.
Find the interquartile range.
15.
Find the standard deviation.
17.
Which of these is equal to 0.32 according to the tree diagram?
F. P(C and B)
G. P(C | B)
H. P(B | C)
J. P(A and C)
18. A spinner has twenty equal-size sections numbered from 1 to 20. If you spin the spinner, what is the probability
that the number you spin will be a multiple of 2 or a multiple of 3?
19. A box contains 20 red marbles and 30 blue marbles. A second box contains 10 white marbles and 47 black marbles.
If you choose one marble from each box without looking, what is the probability that you get a blue marble and a black marble?
20.
Of 50 people who rented clubs at a golf course, 38 were right-handed.
a. Find the sample proportion as a percent.
b. Find the margin of error.
c. Find an interval likely to contain the true population proportion.
21. A set of data has a normal distribution with a mean of 29 and a standard deviation of 4.
Find the percent of data within each interval.
a. from 25 to 33
b. from 21 to 25
c. greater than 29
22.
A data set has a z-score of 4 for the value 55 and a mean of 35.
Find the standard deviation.
Four hundred retired athletes participate in a 10-km run. The runners’ ages are normally distributed with a mean of 72 yr and a
standard deviation of 10. Find the approximate number of runners with ages in each interval.
23.
between 72 and 82 yr
24.
less than 72 yr
25.
A set of data with a mean of 58 and a standard deviation of 6.3 is normally distributed.
Find the value that is 2 standard deviations below the mean.
26.
Choose the poll that is the least biased.
A. A student stands outside an expensive restaurant and asks customers whether they are for or against welfare.
B. A magazine for bird lovers asks subscribers how many cats they own.
C. A researcher asks students in Hawaii whether they own snowmobiles.
D. A researcher stands outside a grocery store and asks shoppers whether they spend more or less than $100/wk on food.
27. Weather data for the past 30-55 years (depending on the city) has recorded the number of sunny, partly sunny, and cloudy
days is available from the National Weather service. The mean number of sunny, or partly sunny days was 219 days with a
standard deviation of approximately 18 days and the distribution of sunny days can be roughly modeled by a normal distribution.
(Note: no city realistically had sunshine 365 days of the year.)
What percent of the data is above 183 days?
Bias is present in the following sampling design.
In the specified case, identify the type of bias involved and state what the problem using the specified design is.
28. Based on a survey of 4113 U.S. Adults, researchers at Stanford University concluded that Internet use leads to increased
social isolation. The survey was conducted by an Internet-based polling company that selected its samples from a pool of 35,000
potential respondents, all of whom have been given free internet access and WebTV hardware in exchange for agreeing to
regularly participate in surveys conducted by the polling company.
29. We wish to draw a sample of 5 without replacement from a population of 50 households. Suppose the households are
numbered 01, 02, . . . , 50, and suppose that the relevant line of the random number table is 11362 35692 96237 90842 46843
62719 64049 17823.
Then the households selected are
(a) households 11 13 36 62 73 (b) households 11 36 23 08 42 (c) households 11 36 23 23 08
(d) households 11 36 23 56 92 (e) households 11 35 96 90 46
Key:
1. 1/5 or 20%
2. 3/10 or 30%
3. ½ or 50%
4. 27/32 or 84.4%
5. Not Mut. Exc. ¾ or 75%
6. Mut. Exc 8/8 or 100%
7. 9/100 or 9%
8. 16/29 or 55.1%
9. ½ or 50%
10. 1/35 or 2.9%
11. Mean 96.55; Median 99; Mode 90 and 99
12. LE=87 LQ=90 Med=99 UQ=102 UE=104
Picture???
13. 17
14. 12
15. 5.99
16. 30th = 90 80th = 102
17. F
18. 13/20 or 65%
19. 47/95 or 49.5%
20. a. 38/50 or 76%
b. +/- 14%
c. 62%-90%
21. a. 68% b. 13.5% c. 50%
22. 5
23. 34%
24. 50%
25. 45.4
26. D
27. 97.5%
28. Discuss in class
29. B