# Question 1 Let x represent the number of pets in pet stores. This would be considered what type of variable:

**Question 1**

Let x represent the number of pets in pet stores. This would be considered what type of variable:

Nonsensical

Continuous

Lagging

Discrete

**Question 2**

Let x represent the number of players on a sports field. This would be considered what type of variable:

Discrete

Continuous

Distributed

Inferential

**Question 3**

Consider the following table.

Age GroupFrequency18-29983130-39784540-49686950-59632360-69541070 and over5279

If you created the probability distribution for these data, what would be the probability of 30-39?

18.9%

42.5%

16.5%

23.7%

**Question 4**

Consider the following table.

Weekly hours workedProbability1-30 (average=23)0.0831-40 (average=36)0.1641-50 (average=43)0.7251 and over (average=54)0.04

Find the mean of this variable.

39.0

39.5

41.6

40.0

**Question 5**

Consider the following table.

Defects in batchProbability00.0910.2420.4130.1240.1050.04

Find the variance of this variable.

2.02

1.43

1.22

1.48

**Question 6**

Consider the following table.

Defects in batchProbability20.3530.2340.2050.0960.0770.06

Find the standard deviation of this variable.

3.48

2.27

4.50

1.51

**Question 7**

The standard deviation of the number of video game A’s outcomes is 1.8940, while the standard deviation of the number of video game B’s outcomes is 1.6179. Which game would you be likely to choose if you wanted players to have the most choice and why?

Game B, as the standard deviation is lower and, thus offers more choices in outcomes

Game A, as the standard deviation is lower and, thus offers fewer choices in outcomes

Game A, as the standard deviation is higher and, thus offers fewer choices in outcomes

Game B, as the standard deviation is higher and, thus offers more choices in outcomes

**Question 8**

Thirty-five percent of teens buy soda (pop) at least once each week. Eleven kids are randomly selected. The random variable represents the number of these kids who purchase soda (pop) at least once each week. For this to be a binomial experiment, what assumption needs to be made?

The probability of being a teen and being a kid should be the same

All the kids eligible to be selected are teens

All eleven kids selected live in the same region

All teens have the same probability of being selected

**Question 9**

A survey found that 39% of all gamers play video games on their smartphones. Ten frequent gamers are randomly selected. The random variable represents the number of frequent games who play video games on their smartphones. What is the value of n?

0.10

x, the counter

0.39

10

**Question 10**

Thirty-five percent of US adults have little confidence in their cars. You randomly select ten US adults. Find the probability that the number of US adults who have little confidence in their cars is (1) exactly six and then find the probability that it is (2) more than 7.

(1) 0.069 (2) 0.005

(1) 0.069 (2) 0.974

(1) 0.021 (2) 0.026

(1) 0.021 (2) 0.005

**Question 11**

Say a business found that 98.3% of soda cans at a production facility in California are filled correctly. The company chooses 100 juice cans off the production line at that same facility. What assumption must be made for this study to follow the probabilities of a binomial experiment?

That the probability of being a selected can is the same for both products

That the probabilities of soda cans and juice cans being filled correctly is the same

That the probability of cans being filled correctly is the same as the probability of a can being selected

That there is a 98.3% probability of being a selected customer in either production line

**Question 12**

Eleven baseballs are randomly selected from the production line to see if their stitching is straight. Over time, the company has found that 98.3% of all their baseballs have straight stitching. If exactly nine of the eleven have straight stitching, should the company stop the production line?

No, the probability of nine or more having straight stitching is not unusual

Yes, the probability of nine or less having straight stitching is unusual

No, the probability of exactly nine have straight stitching is not unusual

Yes, the probability of exactly nine having straight stitching is unusual

**Question 13**

A beer company puts 15 ounces of beer in each can. The company has determined that 95.5% of cans have the correct amount. Which of the following describes a binomial experiment that would determine the probability that a case of 16 cans has all cans that are properly filled?

n=15, p=0.95, x=16

n=15, p=0.955, x=15

n=16, p=0.955, x=16

n=16, p=0.95, x=1

**Question 14**

A supplier must create metal rods that are 16.4 inches long to fit into the next step of production. Can a binomial experiment be used to determine the probability that the rods are too long, too short, or about right?

Yes, all production line quality questions are answered with binomial experiments

Yes, as each rod measured would have two outcomes: too long or too short

No, as there are three possible outcomes, rather than two possible outcomes

No, as the probability of being about right could be different for each rod selected

**Question 15**

In a box of 12 pens, there is one that does not work. Employees take pens as needed. The pens are not returned, once taken. You are the 5th

employee to take a pen. Is this a binomial experiment?

Yes, the probability of success is one out of 12 with 5 selected

No, the probability of getting the broken pen changes as there is no replacement

No, binomial does not include systematic selection such as “fifth”

Yes, you are finding the probability of exactly 5 not being broken

**Question 16**

Forty-two percent of employees make judgements about their co-workers based on the cleanliness of their desk. You randomly select 7 employees and ask them if they judge co-workers based on this criterion. The random variable is the number of employees who judge their co-workers by cleanliness. Which outcomes of this binomial distribution would be considered unusual?

0, 1, 7

1, 6, 7

1, 2, 6, 7

0, 1, 2, 7

**Question 17**

Sixty-eight percent of products come off the line within product specifications. Your quality control department selects 15 products randomly from the line each hour. Looking at the binomial distribution, if fewer than how many are within specifications would require that the production line be shut down (unusual) and repaired?

Fewer than 11

Fewer than 8

Fewer than 9

Fewer than 10

**Question 18**

The probability of a potential employee passing a drug test is 91%. If you selected 15 potential employees and gave them a drug test, how many would you expect to pass the test?

13 employees

14 employees

15 employees

12 employees

**Question 19**

The probability of a potential employee passing a training course is 86%. If you selected 15 potential employees and gave them the training course, what is the probability that 12 or less will pass the test?

0.852

0.148

0.862

0.100

**Question 20**

Off the production line, there is a 3.7% chance that a candle is defective. If the company selected 45 candles off the line, what is the probability that fewer than 3 would be defective?

0.037

0.916

0.975

0.768