Geometric vs. Binomial

1.

Multiple Choice

30 sec

1 pt

The American Red Cross says that about 11% of the U.S. population has Type B blood. A blood drive is being held at your school. How many blood donors should the American Red Cross expect to collect from until it gets a donor with Type B blood?

9.1 donors

8.5 donors

10.3 donors

Cannot be determined.

2.

Multiple Choice

1 min

1 pt

The American Red Cross says that about 11% of the U.S. population has Type B blood. A blood drive is being held at your school. What is the probability that the tenth blood donor is the first donor with Type B blood?

approximately 0.00

0.316

0.0385

0.279

3.

Multiple Choice

30 sec

1 pt

The American Red Cross says that about 11% of the U.S. population has Type B blood. A blood drive is being held at your school.What is the probability that exactly 2 of the first 20 blood donors have Type B blood?

0.316

0.282

0.001

Not here

4.

Multiple Choice

30 sec

1 pt

The American Red Cross says that about 11% of the U.S. population has Type B blood. A blood drive is being held at your school. What is the probability that at least 2 of the first 10 blood donors has Type B blood?

0.088

0.697

0.214

0.303

5.

Multiple Choice

30 sec

1 pt

We calculate the probability of rolling a 6 for the first time on the 6^th roll of a die using the binomial distribution?

True

False

6.

Multiple Choice

30 sec

1 pt

A September 2011 Gallup survey suggests that 38% of Americans are planning on voting for Barack Obama in the 2012 presidential election. Among a random sample of 100 people, approximately how many would you expect to vote for Obama?

38 people

42 people

6 people

Cannot be determined

7.

Multiple Choice

1 min

1 pt

Which of the following is true about geometric distributions?

Geometric distributions are approximately skewed right.

Geometric distributions are approximately symmetric.

Geometric distributions are approximately skewed left.

The shape could be symmetric or skewed.

8.

Multiple Choice

1 min

1 pt

Which of the following is false about binomial probabilities?

Their distributions are approximately symmetric.

Trials must be fixed.

Events musts be independent.

The probability of success must be 0.50

9.

Multiple Choice

30 sec

1 pt

A test consists of 10 multiple choice questions with five choices for each question. As an experiment, you GUESS on each and every answer without even reading the questions.
What is the probability of getting exactly 6 questions correct on this test?

0.6%

0.00001%

0.0064%

0.0002%

10.

Multiple Choice

30 sec

1 pt

When rolling a fair die 100 times, what is the probability of rolling a "4"exactly 25 times?

0.010

0.167

0.25

0.021

11.

Multiple Choice

30 sec

1 pt

At a certain intersection, the light for eastbound traffic is red for 15 seconds, yellow for 5 seconds, and green for 30 seconds. Find the probability that out of the next eight eastbound cars that arrive randomly at the light,exactly three will be stopped by a red light.

0.254

0.147

0.027

0.1940

12.

Multiple Choice

30 sec

1 pt

The owner of a pet store is trying to decide whether to discontinue selling specialty clothes for pets. She suspects that only 4% of the customers buy specialty clothes for their pets. What is the probability that she does NOT sell a garment until the 7th customer? Assume each customer is independent.

0.033

0.027

0.0313

Not here

13.

Multiple Choice

30 sec

1 pt

Which one of these variables is a continuous random variable?

The time it takes a randomly selected student to complete an exam.

The number of tattoos a randomly selected person has.

The number of women taller than 68 inches in a random sample of 5 women.

The number of correct guesses on a multiple choice test.

14.

Multiple Choice

1 min

1 pt

The owner of a pet store is trying to decide whether to discontinue selling specialty clothes for pets. She suspects that only 4% of the customers buy those clothes. The owner had 275 customers that day. Assuming this was a typical day, what is the mean and standard deviation of customers who buy specialty clothes?

11 customers, give or take 3.25

25 customers, give or take 24.5

11 customers, give or take 3.32

Not enough information.

15.

Multiple Choice

30 sec

1 pt

The owner of a small convenience store is trying to decide whether to discontinue selling magazines. He suspects that only 5% of the customers buy a magazine and thinks that he might be able to use the display space to sell something more profitable. What is the probability that at least 5 of his first 50 customers buy magazines?

0.104

0.896

0.066

0.774

16.

Multiple Choice

30 sec

1 pt

Which one of these variables is a binomial random variable?

Time it takes a randomly selected student to complete a multiple choice exam

Number of textbooks a randomly selected student bought this term

Number of women taller than 68 inches in a random sample of 5 women

Number of CDs a randomly selected person owns

17.

Multiple Choice

30 sec

1 pt

Suppose that a quiz consists of 20 True-False questions. A student hasn't studied for the exam and will just randomly guesses at all answers (with True and False equally likely). How would you find the probability that the will student get 8 or fewer answers correct? √

Find the probability that X=8 in a binomial distribution with n = 20 and p=0.5.

Find the area between 0 and 8 in a uniform distribution that goes from 0 to 20.

Find the probability that X=8 for a normal distribution with mean of 10 and standard deviation of √5

Find the cumulative probability for 8 in a binomial distribution with n = 20 and p = 0.5.

18.

Multiple Choice

30 sec

1 pt

A medical treatment has a success rate of 0.8. Two patients will be treated with this treatment. Assuming the results are independent for the two patients, what is the probability that neither one of them will be successfully cured?

0.5

0.36

0.2

0.04

Explore this activity with a free account