Prob & Stat Final Exam

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

A survey found that 25% of pet owners had their pets bathed professionally rather than do it themselves. If 18 pet owners are randomly selected, find the probability that exactly 5 people have their pets bathed professionally

• 3.42
• 1.03
• 0.072
• 0.199

Which of the following is NOT an assumption of the Binomial distribution?

• All trials must be independent.
• Each trial must be classified as a success or a failure.
• All trials are dependent on each other.
• The number of successes in the trials is counted.

An algebra 2 test has 6 multiple choice questions with four choices with one correct answer each. If we just randomly guess on each of the 6 questions, what is the probability that you get exactly 3 questions correct? (You need to figure out the p value first. It is not given to you.)

• 0.962
• 0.132
• 0.831
• 0.250

Bob is taking a 100 question test.  They have a 90 % probability of getting any one question correct.  WHICH IS THE CORRECT FORMULA TO FIND OUT THE PROBABILITY that they will answer EXACTLY 70  questions correctly?

• ₁₀₀C₇₀   ( 0.18  )³⁰ ( 0.90  )⁷⁰
  
• ₁₀₀C₇₀   ( 0.10  )³⁰ ( 0.90  )⁶⁰
• ₁₀₀C₇₀   ( 0.10  )³⁰ ( 0.90  )⁷⁰
• ₉₉C₇₀   ( 0.10  )³⁰ ( 0.90  )⁷⁰

32 percent of beach goers end up with some form of sunburn on any given day. Find the mean of a survey of 75 beach goers.

• 25

• 24

• 2600

• I don't go to the beach

Evaluate $_8C_5$  

• 336

• 56

• 8/5

• 40,320

What is the probability of tossing a coin 5 times and having it land tails-side-up 4 of the 5 times?

• 7.8 %

• 80 %

• 1.6 %

• 20 %

At a certain restaurant, there is a 70% probability that the flowers on your table will be yellow. If you are there with a group that is occupying 6 tables, what is the probability that 5 of the tables will have yellow flowers?

• 70%

• 70.6 %

• 30.3 %

• 5.0 %

If you are randomly selecting a day, the probability of selecting a Saturday is 1/7. If 10 days are randomly selected, what is the standard deviation?

• 1.22

• 1

• 1/7

• 1.11