Binomial and Normal Distributions Review

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

• All trials must be independent.
• Each trial has only two outcomes: success or failure

• All trials are dependent on each other.
• The number of successes in the trials is counted.

Is the distribution below a probability distribution? Why or why not?

• Yes. All P(x) values are between 0 and 1, and ∑P(x) = 1
• No, not all P(x) values are between 0 and 1.
• No, ∑P(x) ≠ 1.

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. 

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 less than 2 of the first 10 blood donors has Type B blood? 

• 0.088
• 0.697
• 0.214
• 0.303 

Find the mean of a binomial distribution with n=50 and p=0.4

• 50

• 4

• 20

• 10

Find the standard deviation of a binomial distribution with n=50 and p=0.4 (Round to the nearest tenth)

• 4.2

• 3.5

• 12.0

• 6.2

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

On the graph from points -1 to 1, what is the percentage?

• 99.7%

• 34%

• 95%

• 68%

Find the z-score

x = 36 μ= 42 σ = 5

• 0.74

• 1.2

• -1.2

• 1.03

Find the z-score

x = 19 μ= 14 σ = 2.1

Type in your answer to the nearest hundredth