# AP Stats Exam Review Flashcards

1

Q

when do you use binomial distribution?

A

- fixed number of trials (n)
- 2 outcomes, success and failure
- probability of success the same for each trial

Want to know “what is the probability of X successes in n trials”

2

Q

Binomial Distribution–20 trials, probability of success = 0.35, what is the probability of 5 successes?

A

Calculator:

binomialpdf(20, .35. 5)

3

Q

Binomial Distribution–20 trials, probability of success = 0.35, what is the probability of 5 successes or less?

A

Calculator:

binomialcdf(20, .35, 5)

4

Q

What is stratified sampling?

A

Divide the whole group into subgroups, such as high school into freshman, sophomores, juniors seniors, or a whole group into males and females, randomly sample from each group