# static by uc86

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```									   1. A coin is tossed, and you win \$1 if you get less than 40% heads. How many tosses should
you make?

a. 10
b. 100

1.33 points

Question 2

1.

A box has three red balls and four green balls. A gambler bets \$1 on red. A ball is
randomly chosen. The gambler win \$1 if the ball is red, otherwise he loses \$1. He will
play this game 200 times. The SE for the gambler's net gain is:

a. \$52.70
b. \$15.56
c. \$54.13
d. \$42.12
e. \$14.00

1.33 points

Question 3

1.

If a set of numbers has an average of 15 and an SD of 3, and each number in the set is
multiplied by 4, what will the SD of the new set of numbers be?

a. 12
b. 60
c. 10
d. 7
e. 14
1.33 points

Question 4

1.

A spinner has three numbers on it(1,2,3). Each number has an equal probability of being
hit on each spin. A person bets \$1 to play the game. He picks a number, then he spins. If
his number comes up, he wins \$2. He plays this game 100 times. What would be the
average amount won per spin on the spinner?

a. \$100
b. \$200
c. \$0.00
d. \$1.00
e. -\$1.00

1.34 points

Question 5

1.

For gambling problems in which the same bet is made several times, a box model is set
up so that the tickets in the box show the amounts that can be won (+) or lost (-) and the
chance of drawing any particular value from the box equals the chance of winning that
amount on a single play. In this scenario, the following statement is true or false: Now
the number of draws equals the number of tickets in the box.

False

1.34 points

Question 6

1.

A gambler plays roulette 200 times, betting \$1 on a split each time. A split pays 17 to 1,
and there are 2 ways in 38 to win. (We are interested in the the casino making more than
\$10.) Find the casino's standard error for the sum.

a. \$56.84
b. \$3.10
c. none of these
d. \$4.02
e. \$10.53

1.33 points

Question 7

1.

A random sample of 15 people is taken and their weights are: 145, 128, 198, 156, 144,
178, 114, 104, 289, 250, 166, 148, 122, 188, 156. Find the interquartile range.

32
56
none of these
99
185

1.33 points

Question 8

1.

Find the area under the Normal Curve from -2.5 to 1.1.

a. 82.85%
b. 98.76%
c. 25.89%
d. 12.95%
e. 72.87%
1.33 points

Question 9

1.

A pharmaceutical company wants to study the effectiveness of a drug. The company
uses a placebo in the study. In order to distinguish the drug pill from the placebo pill, the
company should use a color for the placebo pill that is different from the color of the drug
pill.

True
False

1.33 points

Question 10

1.

Two dice are thrown. What is the probability that at least one of the two dice is a
"three"?

1/18
2/3
1/3
11/36
1/6

1.33 points

Question 11

1.

One hundred draws are made at random with replacement from the box with tickets
showing numbers 2, 5, 8. How small can the sum of the draws be?

0
2
200
500
100

1.33 points

Question 12

1.

The law of averages stated in percentage terms, in case of a rolling a die, will be: with a
large number of rolls, the percentage of aces(a single spot), is likely to be close to
16.67%

False

1.33 points

Question 13

1.

The population of interest for "Dancing with the Stars" is all of the people who watched
the show. From this population, people call in for their favorite. What is the best
description of bias that takes place?

a. simple random sampling
b. none of these
c. cluster bias
d. non-response bias
e. selection bias

1.34 points

Question 14

1.
A gambler plays roulette, and makes a \$1 bet on four numbers, 400 times. The bet pays 8
to 1. Find the chance that the casino will win between \$30 and \$40.

a. 63.69%
b. 7.88%
c. 15.45%
d. 83.85%
e. 7.73%

1.34 points

Question 15

1.

The probability histogram for the average of the draw will follow the normal curve, even
if the contents of the box do not, as long as the histogram is put into standard units, and
the number of draws is large.

a. True
b. False

1.34 points

Question 16

1.

The GPA of students in a large university follows a normal distribution with an average
of 3.05 and SD of 0.45. The upper quartile is about:

a. 3.21
b. 3.74
c. 3
d. 2.95
e. 3.34
1.33 points

Question 17

1.

A gambler plays roulette 200 times, betting \$1 on a split each time. A split pays 17 to 1,
and there are 2 chances in 38 to win. Find the chance that the casino makes more than
\$10 from these plays.

a. 7.5%
b. 24.56%
c. 69.19%
d. 50.00%
e. 3.60%

1.33 points

Question 18

1.

A researcher wants to study the spending habits of customers of a local shopping mall.
The mall manager claims that the average spending per customer is \$70, but the
researcher believes that the average is less than \$70. A simple random sample of 350
shoppers is obtained. The sample average is \$65 and the sample SD is \$27. Find the null
hypothesis.

a. the sample average is less than \$70
b. the population average is \$70
c. none of these
d. the population average is less than \$70
e. the population average is greater than \$70

1.33 points

Question 19
1.

A box contains two red marbles and three white marbles. Two marbles are drawn
without replacement. What is the chance that the second one is red given that the first
one is red?

1/2
1/4
1/10
1/5
2/5

1.33 points

Question 20

1.

There are 10 workers and 2 administrators in a company meeting room. Two people will
be selected at random without replacement. The chance that the second person is a
worker given that the first person is an administrator is:

a. 5/6
b. none of these
c. 5/33
d. 10/11
e. 15/66

1.33 points

Question 21

1.

When a medical study compares a present-day group undergoing a newly developed
procedure with patients in the past who received more traditional care, the study has
______________.

controlled error
response bias
gender bias
historical controls
none of these

1.33 points

Question 22

1.

The standard deviation is a measure of ________________.

b. center

1.33 points

Question 23

1.

As a person increases the number of tosses of a fair coin, the actual number of heads will
get further and further away from the number of tosses divided by two.

a. False
b. True

1.34 points

Question 24

1.
In a month, there are 7,000 independent plays on a roulette wheel in a certain casino.
Suppose the gamblers only stake \$1 on red at each play. (Red or black pays even
money.) We ultimately want to find the chance that the house will win more than \$300
from these plays. Find the standard error for the sum.

\$83.56
\$50.00
\$21.66
\$41.78
\$99.86

1.33 points

Question 25

1.

A gambler plays roulette, and makes a \$1 bet on four numbers, 400 times. The bet pays 8
to 1. Find the standard error for the sum.

a. \$15.80
b. \$61.76
c. none of these
d. \$55.24
e. \$56.76

1.34 points

Question 26

1.

Two persons, X and Y, watch the tossing of a fair coin by a common friend, Z. The first
ten tosses turn up to be heads. Now X says that in order for law of average to be true, the
11th toss has to be a tail. But Y says that in view of the pattern seen so far, the 11th toss
has to be a head. Select the correct conclusion from the list of statements below:

Both X and Y are correct
Only Y is correct
Only X is correct
Both X and Y are incorrect
Who tosses the coin matters

1.33 points

Question 27

1.

A researcher wants to study the spending habits of customers of a local shopping mall.
The mall manager claims that the average spending per customer is \$70, but the
researcher believes that the average is less than \$70. A simple random sample of 350
shoppers is obtained. The sample average is \$65 and the sample SD is \$27. Find the
alternative hypothesis.

a. the population average is greater than \$70
b. the population average is \$70
c. the sample average is less than \$70
d. the population average is less than \$70
e. none of these

1.33 points

Question 28

1.

There are 300 total test papers.

Test Score Intervals                Frequency Percent

90-100                                36           _____

80-90                                ____           20

70-80                                138            46
60-70                               45           ____

50-60                              _____          7

For the histogram that could be created relative to the previous table, find the height of
the block over 90-100.

a. 1.2%
b. 4%
c. 12%
d. 2.5%
e. 36%

1.33 points

Question 29

1.

The purpose of randomization is to minimize bias.

False

1.33 points

Question 30

1.

The GPA of students in a large university follows a normal distribution with an average
of 3.05 and an SD of 0.45. Find the 90th percentile.

a. 3.05
b. 3.90
c. 4.00
d. 3.22
e. 3.64

1.33 points

Question 31

1.

In a month, there are 7,000 independent plays on a roulette wheel in a certain casino.
Suppose the gamblers only stake \$1 on red at each play. (Red or black pays even
money.) Find the chance that the house will win more than \$300 from these plays.

21%
79%
85%
29%
58%

1.33 points

Question 32

1.

A researcher wants to study the spending habits of customers of a local shopping mall.
The mall manager claims that the average spending per customer is \$70, but the
researcher believes that the average is less than \$70. A simple random sample of 350
shoppers is obtained. The sample average is \$65 and the sample SD is \$27. Should we
believe the mall manager's claim?

a. No
b. Yes

1.33 points

Question 33

1.
For the women age 18-24 in the HANES2 sample, the average height was about 65.2
inches, and the SD was about 1.9 inches. Estimate the percentage of women with heights
above 65 inches.

a. 46.02%
b. 7.97%
c. 53.99%
d. 92.03%
e. 68.27%

1.33 points

Question 34

1.

A group of 50,000 tax forms has 20% with gross income over \$50,000. A group of 900
forms is chosen at random for audit. A box model is used to work out the expected value
and the standard error for the percentage of people with incomes over \$50,000 in the
sample. Choose what best describes "sample size".

a. Box
b. Percentage of 1s among the draws
c. 180
d. 20%
e. 900

1.34 points

Question 35

1.

A rope manufacturer claims that is brand has a breaking strength of 1500 lbs. A
consumer agency wishing to test the claim took a simple random sample of 225 ropes,
and found the average breaking strength to be 1425 with a standard deviation of 400 lbs.
Report the Standard error for the average.

43.45
2.56
29.73
26.67
1.33

1.34 points

Question 36

1.

A card is picked at random from an ordinary deck. What is the probability that it is a jack
given that it is a face card?

1/4
1/3
1/12
1/13
1/2

1.33 points

Question 37

1.

The GPA of students in a large university follows a normal distribution with an average
3.05 and SD of 0.45. Find the chance that a student's GPA is greater than 3.5.

a. 32%
b. 68%
c. 95%
d. 14.89%
e. 16%

1.34 points

Question 38

1.

Find the probability that three cards are drawn from a deck, and you get two reds,
followed by a black.

a. 13/102
b. 1/11050
c. 1/5100
d. none of these
e. 169/1020

1.34 points

Question 39

1.

A researcher wants to study the spending habits of customers of a local shopping mall.
The mall manager claims that the average spending per customer is \$70, but the
researcher believes that the average is less than \$70. A simple random sample of 350
shoppers is obtained. The sample average is \$65 and the sample SD is \$27. We should
_________ the null hypothesis.

a. Reject
b. Accept

1.33 points

Question 40

1.
The average on an exam was 23.5 and the SD was 5.5. Use the normal curve to estimate
the percentage of students who made between 18 and 29.

a. 68.27%
b. 20%
c. 55%
d. 95.43%
e. 16.64%

1.33 points

Question 41

1.

A rope manufacturer claims that is brand has a breaking strength of 1500 lbs. A
consumer agency wishing to test the claim took a simple random sample of 225 ropes,
and found the average breaking strength to be 1425 with a standard deviation of 400 lbs.
Should we accept or reject the null hypothesis?

accept
reject

1.33 points

Question 42

1.

A rope manufacturer claims that is brand has a breaking strength of 1500 lbs. A
consumer agency wishing to test the claim took a simple random sample of 225 ropes,
and found the average breaking strength to be 1425 with a standard deviation of 400 lbs.
Find the value of the test statistic.

2.15
none of these
-2.81
-1.19
-0.98

1.34 points

Question 43

1.

A rope manufacturer claims that is brand has a breaking strength of 1500 lbs. A
consumer agency wishing to test the claim took a simple random sample of 225 ropes,
and found the average breaking strength to be 1425 with a standard deviation of 400 lbs.
Find the best conclusion.

the p-value is too large, do not reject the manufacturer's claim
none of these
the result is statistically significant, so reject the manufacturer's claim
the result is inconclusive, so try another sample
this result is highly significant, so reject the manufacturer's claim

1.33 points

Question 44

1.

The heights of the men age 18 and over in the HANES sample averaged 68.5 inches; the
SD was 2.9 inches. Use the normal curve to estimate the percentage of these men with
heights between 65 and 68 inches.

a. 32.54%
b. 44.46%
c. none of these
d. 76.99%
e. 11.92%
1.33 points

Question 45

1.

We toss a die 300 times. What is the chance that we get more than sixty 3s?

a. 87.90%
b. 0.35%
c. 6.06%
d. 12.11%
e. 87.89%

1.34 points

Question 46

1.

A gambler plays roulette, and makes a \$1 bet on four numbers, 400 times. The bet pays 8
to 1. Find the SD of the box model that would go with this situation.

a. \$56.75
b. none of these
c. \$2.76
d. \$61.76
e. \$5.37

1.33 points

Question 47

1.

A confounding factor is a third variable that affects the responses. There is no way to
control the confounding factor.

True
False

1.33 points

Question 48

1.

We toss a die 300 times. Find the standard error for the expected number of 3s.

a. 6.45
b. 0.022
c. 3.73
d. 7.06
e. 0.3727

1.34 points

Question 49

1.

A probability histogram represents chance by area.

a. True
b. False

1.34 points

Question 50

1.

A random sample of 15 people is taken and their weights are: 145, 128, 198, 156, 144,
178, 114, 104, 289, 250, 166, 148, 122, 188, 156. There is(are) __________ outlier(s).

1
3
2
0
none of these

1.33 points

Question 51

1.

Sixteen people in a room have an average height of 5'6". A seventeenth person enters the
room. How tall would he have to be to raise the average height by one inch?

a. 5'8"
b. 6"11"
c. 6'2"
d. 6'1"
e. 6'5"

1.33 points

Question 52

1.

Arlington voters have recently approved the Cowboys stadium near the Ameriquest
Field. The project would require the relocation of some homeowners. The city council
voted that these homeowners will be paid \$22,500, fair-market value for their houses and
moving expenses. A researcher wants to find out Arlington residence opinion whether
the compensation is fair to these homeowners. He randomly selects 30 homeowners for
relocation and 30 other Arlington citizens. He then compares the opinions of the two
groups. This is a(n) _________________.

observational study
randomized controlled experiment

1.33 points

Question 53

1.

The GPA of students in a large university follows a normal distribution with an average
of 3.05 and SD of 0.45. The chance that a student's GPA is between 2.5 and 3.5 is:

a. 48%
b. 90%
c. 68%
d. 39%
e. 73%

1.33 points

Question 54

1.

There are 10 workers and 2 administrators in a company meeting room. Two people will
be selected at random without replacement. The chance that both are administrators is:

a. none of these
b. 1/3
c. 1/66
d. 2/33
e. 1/36

1.34 points

Question 55

1.
A researcher wants to study the spending habits of customers of a local shopping mall.
The mall manager claims that the average spending per customer is \$70, but the
researcher believes that the average is less than \$70. A simple random sample of 350
shoppers is obtained. The sample average is \$65 and the sample SD is \$27. Find the SE
for the sample average.

a. 5.08
b. 1.44
c. 1.34
d. 1.27
e. 2.91

1.33 points

Question 56

1.

In a month, there are 7,000 independent plays on a roulette wheel in a certain casino.
Suppose the gamblers only stake \$1 on red at each play. (Red or black pays even
money.) We ultimately want to find the chance that the house will win more than \$300
from these plays. Find the expected value for the sum .

\$459.91
\$368.42
\$105.78
-\$368.42
\$526

1.33 points

Question 57

1.

Liver cancer is more common among people who smoke, so we conclude that smoking
causes liver cancer.

True
False

1.33 points

Question 58

1.

In a month, there are 7,000 independent plays on a roulette wheel in a certain casino.
Suppose the gamblers only stake \$1 on red at each play. (Red or black pays even
money.) We ultimately want to find the chance that the house will win more than \$300
from these plays. What is 300 in standard units?

2
-0.82
-0.69
1
-1.63

1.33 points

Question 59

1.

Bias occurs systematically, so we can not eliminate the systematic error.

False

1.33 points

Question 60

1.

In cluster sampling, the sample is hand-picked to resemble the population.

a. False
b. True

1.34 points

Question 61

1.

A die will be rolled some number of times, and you win \$1 if it shows a three less than
25% of the time. Which is better?

a. 70 rolls
b. 700 rolls

1.33 points

Question 62

1.

A gambler bets \$1 on the number "19" 1600 times in roulette. This bet pays 35 to 1. What
is the give-or-take on the estimate of his winnings?

a. \$230.50
b. \$184.25
c. \$84.36
d. \$23.50
e. \$96.58

1.34 points

Question 63

1.
Bias in measurement theory is called ____________.

a. sampling error
b. systematic error
c. chance error

1.33 points

Question 64

1.

The sum of the draws from a box is 440. If the average of these draws is 2.20, how many
draws were there?

a. 200
b. 968
c. impossible to tell
d. 880
e. 20

1.33 points

Question 65

1.

A random sample of 15 people is taken and their weights are: 145, 128, 198, 156, 144,
178, 114, 104, 289, 250, 166, 148, 122, 188, 156. True or False: The median is 156.

False

1.34 points

Question 66

1.
A _____________ is taken from the _____________ in order to estimate the
________________.

a. sample, population, statistic
b. population, sample, parameter
c. sample, population, parameter
d. population, sample, statistic

1.33 points

Question 67

1.

In a certain city, there are 100,000 persons age 18 to 24. A simple random sample of 500
such persons is drawn, of whom 198 turn out to be currently enrolled in college. If
possible, find a 95% confidence interval for the percentage of all persons age 18 to 24 in
that city who are currently enrolled in college.

a. none of these
b. 36.72% to 45.48%
c. not possible
d. 35.22% to 43.98%
e. 33.06% to 40.41%

1.34 points

Question 68

1.

A rope manufacturer claims that is brand has a breaking strength of 1500 lbs. A
consumer agency wishing to test the claim took a simple random sample of 225 ropes,
and found the average breaking strength to be 1425 with a standard deviation of 400 lbs.
Find the null hypothesis.

none of these
average breaking strength is greater than 1425 lb.
average breaking strength is less than 1500 lb.
average breaking strength is 1500 lb.
average breaking strength is 1425 lb.

1.34 points

Question 69

1.

In a certain city, there are 100,000 persons age 18 to 24. A simple random sample of 500
such persons is drawn, of whom 198 turn out to be currently enrolled in college. Estimate
the percentage of all persons age 18 to 24 in that city who are currently enrolled in
college.

a. 41.1%
b. 39.2%
c. 38.8%
d. 40%
e. 39.6%

1.34 points

Question 70

1.

A rope manufacturer claims that is brand has a breaking strength of 1500 lbs. A
consumer agency wishing to test the claim took a simple random sample of 225 ropes,
and found the average breaking strength to be 1425 with a standard deviation of 400 lbs.
Find the p-value.

0.51%
3.01%
2%
0.65%

1.34 points

Question 71

1.

A die is rolled 5 times. You win \$1000 for every 'four' that occurs. What is the chance
that you win only on the first and last rolls(and lose on the others0?

125/7776
1/15
1/90
25/7776
2/5

1.33 points

Question 72

1.

A gambler plays roulette, and makes a \$1 bet on four numbers, 400 times. The bet pays 8
to 1. Find the amount of money the CASINO is expected to make.

a. \$52.63
b. \$33.33
c. \$210.53
d. \$-21.05
e. \$21.05

1.33 points

Question 73

1.
Among freshmen at a certain university, scores on the Math SAT followed the normal
curve, with an average of 490 and an SD of 85. Find the 75th percentile of the score
distribution.

510
560
318
615
545

1.34 points

Question 74

1.

A survey is conducted in which the respondents are asked to name their favorite movie in
the previous 5 year period. Their responses are examples of _____________________.

quantitative continuous data
quantitative discrete data
qualitative data

1.33 points

Question 75

1.

You have hired a polling organization to take a simple random sample from a box of
200,000 tickets and estimate the percentage of 1s in the box. Unknown to them, the box
contains 50% 0s and 50% 1s. How far off should you expect them to be if they draw
50,000 tickets?