Binomial PDF

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

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 

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

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

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. 

When rolling two dice, the probability of rolling doubles is ⅙. Suppose that a game player rolls the dice five times, hoping to roll doubles. What is the probability the player gets doubles less than three times in 5 attempts?

• 0.161
• 0.965
• 0.015
• 0.997

Find the mean of the probability distribution.

• 85
• 83.2
• 87.1
• 84.4

Classify: The numbers of cheeseburgers a fast-food restaurant serves each day

• None of these
• Abstract
• Continuous
• Discrete

If you flip one coin and then roll a die, how many possible outcomes can you get?

• 6
• 12
• 7
• 0

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