## MATH 399N Week 5 MyStatLab Quiz (2 Versions)

##### MATH 399N Week 5 MyStatLab Quiz

(Version 1)

1. **Question:** Decide whether the random variable x is discrete or continuous.

x represents the volume of blood drawn for a blood test.

**2. Question: **The table below shows the results of a survey in which 143 men and 144 women workers ages 25 to 64 were asked if they have at least one month’s income set aside for emergencies. Complete parts (a) through (d).

**3. Question: **Complete parts (a) and (b) using the probability distribution below.

The number of overtime hours worked in one week per employee

Overtime hours 0 1 2 3 4 5 6

Probability 0.015 0.061 0.158 0.296 0.235 0.168 0.067

- Find the mean, variance, and standard deviation of the probability distribution.
- Interpret the results in the context of the real-life situation.

**4. Question: **Given that x has a Poisson distribution with μ = 1.9, what is the probability that x = 4?

**5. Question: **For the given pair of events, classify the two events as independent or dependent.

- Getting caught in traffic
- Spilling coffee in the car

**6. Question: **Determine whether the distribution is a discrete probability distribution.

## STATUS

**7. Question: **34% adults say cashews are their favorite kind of nut. You randomly select 12 adults and ask each to name his or her favorite nut. Find the probability that the number who say cashews are their favorite nut is (a) exactly three, (b) at least four, and (c) at most two. If convenient, use technology to find the probabilities.

**8. Question: **A company is conducting a survey to determine how prepared people are for a long-term power outage, natural disaster, or terrorist attacks. The frequency distribution on the right shows the results. Use the table to answer the following question.

What is the probability that the next person surveyed is very prepared?

**9. Question: **Use the frequency distribution to the right, which shows the number of voters (in millions) according to age, to find the probability that a voter chosen at random is in the given age range. Not between 25 and 34 years old

**10. Question: **A state lottery randomly chooses 8 balls numbered from 1 through 45 without replacement. You choose 8 numbers and purchase lottery ticket. The random variable represents the number of matches on your ticket to the numbers drawn in the lottery. Determine whether this experiment is binomial. If so, identify a success, specify the values n, p and q and list the possible values of the random variable x.

**11. Question: **A standard deck of cards contains 52 cards. One card is selected from the deck.

- (a) Compute the probability of randomly selecting a two or eight.
- (b) Compute the probability of randomly selecting a two or eight or jack.
- (c) Compute the probability of randomly selecting an eight or diamond.

**12. Question: **The table below shows the results of a survey that asked 1049 adults from a certain country if they would support a change in their country’s flag. A person is selected at random. Complete parts (a) through (d)………………….continue

- Find the probability that the person opposed the change is female.
- … the probability that the person opposed the change is male.
- Find the probability that the person is not unsure or is female.
- Are the events “being female” and “support” mutually exclusive? Explain.

**13. Question: **During a 52-week period, a company paid overtime wages for 17 weeks and hired temporary help for 7 weeks. During 6 weeks, the company paid overtime and hired temporary help. Complete parts (a) and (b) below.

(a) Are the events “selecting a week that contained overtime wages” and “selecting a week that contained temporary help wages” mutually exclusive?

(b) If an auditor randomly examined the payroll records for only one week, what is the probability that the payroll for that week contained overtime wages or temporary help wages?

**14. Question: **In a sample of 1200 U.S. adults, 188 dine out at a restaurant more than once per week. Two U.S. adults are selected at random from the population of all U.S. adults without replacement. Assuming the sample is representative of all U.S. adults, Complete parts (a) through (d).

**15. Question: **Use technology to (a) construct and graph probability distribution and (b) describe it shape.

The number of computers per household in a small town.

**Computers **0** **1 2 3

**Households **305 284 99 17

**16. Question: **Find the mean, variance, and standard deviation of the binomial distribution with the given values of n and p.

n = 90, p = 0.5

##### MATH 399N Week 5 MyStatLab Quiz

(Version 2)

**1. Question: 3.2.9 **For the given pair of events, classify the two events as independent or dependent.

Randomly selecting a city in Texas

Randomly selecting a country in Texas

**2. Question: 4.2.21 **24% of college students say they use credit cards because of the rewards program. You randomly select 10 college students and ask each to name the reason he or she uses credit cards. Find the probability that the number of college students who say they use credit cards because or the reward program is (a) exactly two, (b) more than two, and (c) between two and five inclusive. If convenient, use technology to find the probabilities.

**3. Question: 4.1.13 **Determine whether the random variable is discrete or continuous.

**4. Question: 4.2.7 **Find the mean, variance, and standard deviation of the binomial distribution with the given values of n and p.

n = 60, p = 0.4

**5. Question: 3.2.8 **The table below shows the results of a survey in which 141 men and 145 women workers ages 25 to 64 were asked if they have at least one month’s income set aside for emergencies. Complete parts (a) through (d).

Men Women Total

Less than one month’s income 65 84 149

One month’s income or more 76 61 137

Total 141 145 286

**6. Question: 3.1.63 **Use the bar graph below, which shows the highest level of education received by employees of a company, to find the probability that the highest level of education for an employee chosen at random is C.

**7. Question: 3.2.23 **In a sample of 1000 U.S adults, 198 dine out at a restaurant more than once per week. Two U.S adults are selected at random from the population of all U.S. adults without replacement. Assuming the sample is representative of all U.S. adults, complete parts (a) through (d).

(a) Find the probability that both adults dine out more than once per week.

(b) Find the probability that neither adults dines out more than once per week.

(c) Find the probability that at least one of the two adults dines out more than once per week.

(d) Which of the events can be considered unusual? Explain. Select all that apply.

**8. Question: 3.3.13 **During a 52-week period, a company paid overtime wages for 17 weeks and hired temporary help for 9 weeks. During 6 weeks, the company paid overtime and hired temporary help. Complete parts (a) and (b) below. Are the events “selecting a week that contained overtime wages” and “selecting a week that contained temporary help wages” mutually exclusive?

(a) If an auditor randomly examined the payroll records for only one week, what is the probability that the payroll for that week contained overtime wages or temporary help wages.

**9. Question: 3.3.18 **You roll a six-sided die. Find the probability of each of the following scenarios.

a. Rolling a 6 or a number greater than 3

b. Rolling a number less than 5 or an even number.

c. Rolling a 6 or an odd number.

**10. Question: 4.1.20 **Use technology to (a) construct and graph probability distribution and (b) describe it shape.

The number of computers per household in a small town

Computers 0 1 2 3

Households 303 276 99 23

**11. Question: 4.1.31 **Complete parts (a) and (b) using the probability distribution below.

The number of overtime hours worked in one week per employee

Overtime hours 0 1 2 3 4 5

Probability 0.015 0.067 0.174 0.297 0.210 0.164

(a) Find the mean, variance, and standard deviation of the probability distribution.

**12. Question: 3.3.25 **The table below shows the results of a survey that asked 2858 people whether they are involved in any type of charity work. A person is … at random from the sample. Complete parts (a) through (e).

Frequently Occasionally Not at all Total

Male 223 453 796 1472

Female 201 440 745 1386

Total 424 893 1541 2858

(a) Find the probability that the person is frequently or occasionally involved in charity work.

(e) Are the events “being female” and “being frequently involved in charity work” mutually exclusive? Explain.

**13. Question: 3.1.32 **A probability experiment consists of rolling a 6-sided die. Find the probability of the event below. Rolling a number less than 6

**14. Question: 4.2.14 **A survey asks 1000 workers, “Has the economy forced you to reduce the amount of vacation you plan to take this year?”Forty-one percent of those surveyed say they are reducing the amount of vacation. Twenty workers participating in the survey are randomly … The random variable represents the number of workers who are reducing the amount of vacation. Decide whether the experiment is a binomial experiment. If it is, identify a success, specify the values of n, p, and list the possible values of the random variable x.

**15. Question: 4.3.6 **Assume the Poisson distribution applies. Use the given mean to find the indicate probability.

Find P(4) when μ = 5.

**16. Question: 4.1.25 **Determine the required value of the missing probability to make the distribution a discrete probability distribution.

x P(x)

3 0.27

4 ?

5 0.46

6 0.08

P(4) ____________ (Type an integer or a decimal.)