AP Stats Probability Review

Front

What is the mean of a random variable?

Back

The mean of a random variable is the average value it takes on, calculated as the sum of all possible values multiplied by their probabilities.

Front

What is the standard deviation of a random variable?

Back

The standard deviation measures the amount of variation or dispersion of a set of values. It indicates how much the values deviate from the mean.

Front

If R and S are independent random variables, how do you find the mean of R - S?

Back

The mean of R - S is calculated as: Mean(R) - Mean(S).

Front

If R and S are independent random variables, how do you find the standard deviation of R - S?

Back

The standard deviation of R - S is calculated as: sqrt(StdDev(R)^2 + StdDev(S)^2).

Front

What is the probability of an event?

Back

The probability of an event is a measure of the likelihood that the event will occur, ranging from 0 (impossible) to 1 (certain).

Front

How do you calculate the probability of picking a non-brown rat from a group of rats?

Back

Probability of not picking a brown rat = (Total rats - Brown rats) / Total rats = (100 - 20) / 100 = 0.8.

Front

What is a binomial distribution?

Back

A binomial distribution models the number of successes in a fixed number of independent Bernoulli trials, each with the same probability of success.

Front

What is the formula for the mean of a binomial distribution?

Back

Front

What is the formula for the mean of a geometric distribution?

Back

Front

What does P(A ∪ B) represent in probability?

Back

P(A ∪ B) represents the probability that either event A or event B occurs.