Binomial Distribution

An algebra 2 test has 6 multiple choice questions with 4 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?

• 0.962

• 0.132

• 0.831

• 0.250

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. 

Find the probability of getting at most 100 5's when rolling an 8 sided die 700 times. 

• .9313

• .9149

• .0851

• .0687

The formula shown produces what result?

• The probability of exactly x successes in n trials

• The probability of no more than x successes in n trials

• The probability of success on any single trial.

• The probability of at least x successes in n trials.

A company states that 2% of its computers are returned for defects.  We take a sample of 100 computers to find the probability of 10 being defective.  Is this a binomial distribution?

• No because there is not a fixed number of trials.

• No because their are more than 2 outcomes.

• Yes since there are a fixed number of independent trials, outcomes in 2 categories, and the probability of defect is constant.

• No since computers would not be independent.

A wildlife biologist examines frogs for a genetic trait they suspect may be linked to sensitivity to industrial toxins in the environment. Previous research had established that this trait is usually found in 1 of every 8 frogs. 

1. The biologist collects and examines a dozen frogs. If the frequency of the trait has not changed, what’s the probability they find the trait in none of the 12 frogs? 

• Binomial Distribution

• Geometric Distribution

Choose the correct sign:

'probability at least 7'

• P(X>7)

• P(X<7)

• P(X≥7)

• P(X≤7)

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

When rolling two dice, the probability of rolling doubles is ⅙. Suppose that a player rolls the dice five times, hoping to roll doubles. Find the probability that the player gets doubles exactly twice in 5 attempts.

• 0.884

• 0.139

• 0.965

• 0.161

If you were to flip a coin 20 times, what is the probability you would get exactly 10 heads?

• 50%

• 17.62%

• .58.81%

• 41.19%