Stats Unit 5 Flashcard on Probability

Front

What is the empirical rule in statistics?

Back

The empirical rule states that for a normal distribution, approximately 68% of the data falls within one standard deviation of the mean, 95% falls within two standard deviations, and 99.7% falls within three standard deviations.

Front

What is the mean in statistics?

Back

The mean is the average of a set of numbers, calculated by adding all the values together and dividing by the number of values.

Front

How do you calculate the probability of an event?

Back

Probability is calculated as the number of favorable outcomes divided by the total number of possible outcomes.

Front

What is a normal distribution?

Back

A normal distribution is a probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean.

Front

What does standard deviation measure?

Back

Standard deviation measures the amount of variation or dispersion in a set of values.

Front

How many combinations of 4 engineers can be selected from a group of 12?

Back

495 combinations.

Front

What percentage of data falls within 2 standard deviations in a normal distribution?

Back

Approximately 95% of the data falls within 2 standard deviations of the mean.

Front

What is the formula for combinations?

Back

The formula for combinations is C(n, r) = n! / (r!(n - r)!), where n is the total number of items, r is the number of items to choose, and '!' denotes factorial.

Front

What is the probability of selecting a student who plays football only if 4 out of 80 students play football only?

Back

The probability is 4/80 or 1/20.

Front

What is the significance of the mean height of adult US females being 64.5 inches?

Back

It represents the average height, indicating that half of adult females are shorter and half are taller than this value.