Practice Test

Front

What is the expected value in probability?

Back

The expected value is the average outcome of a random variable, calculated as the sum of all possible values, each multiplied by its probability of occurrence.

Front

How do you calculate the number of outfits possible with multiple clothing items?

Back

Multiply the number of options for each clothing item. For example, with 5 pairs of jeans, 8 t-shirts, and 2 pairs of shoes, the total outfits = 5 * 8 * 2 = 80.

Front

What is standard deviation?

Back

Standard deviation is a measure of the amount of variation or dispersion in a set of values. A low standard deviation means that the values tend to be close to the mean, while a high standard deviation means they are spread out over a wider range.

Front

How do you write a probability distribution?

Back

A probability distribution lists all possible outcomes of a random variable and their corresponding probabilities, ensuring that the total probability sums to 1.

Front

How do you calculate permutations for selecting officers from a group?

Back

Use the formula n! / (n - r)!, where n is the total number of items to choose from, and r is the number of items to choose. For selecting a president, vice president, and secretary from 5 people, it is 5! / (5 - 3)! = 60.

Front

What is the formula for expected value in a game of chance?

Back

Expected Value (EV) = (Probability of Winning * Amount Won) + (Probability of Losing * Amount Lost).

Front

What is the difference between combinations and permutations?

Back

Permutations consider the order of selection important, while combinations do not. For example, selecting 3 people from a group of 5 is a permutation if order matters and a combination if it does not.

Front

What is the significance of rounding in statistics?

Back

Rounding is used to simplify numbers for easier interpretation, but it can affect the accuracy of statistical results, especially in calculations like standard deviation.

Front

How do you find the total number of combinations of outfits?

Back

Multiply the number of choices for each category of clothing. For example, if you have 5 jeans, 8 t-shirts, and 2 shoes, the total combinations = 5 * 8 * 2.

Front

What does a probability of 0.5 indicate?

Back

A probability of 0.5 indicates an equal chance of an event occurring or not occurring.