Binomial and Poisson Distribution

A ball manufacturer claims that only 15% of his balls are defective. If Ali has 6 of these balls to play with at a ball game, find the probability at most 4 balls will be defective.

• 0.9941

• 0.0059

• 0.9996

• 0.9527

If X~Po(1.8), find P(2≤X≤4)

• 0.4285

• 0.7983

• 0.5008

• 0.7260

The random variable, X has the binomial distribution X~B(9,0.25), find P(X=4)

• 0.1657

• 0.1168

• 0.2336

• 0.3504

The random variable Y has binomial distribution Y~B(10,0.4). Find P(3<Y<6)

• 0.6665

• 0.7779

• 0.4515

• 0.2508

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.

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 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)

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%

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