Discrete Random Variables

Front

Probability of guessing at least 4 questions correct on a 5-question true-false quiz.

Back

.1875

Front

The table above shows the number of cell phones per household in a small town. Find the mean round to the nearest hundredth.

Back

2.80

Front

Expected value of stock price with probabilities: 40% chance of $50, 35% chance of $60, 25% chance of $70.

Back

$58.50

Front

In a certain community, 30% of households have 1 child, 43% have 2 children, and 27% have 3 children. If a household is selected at random, what is the expected number of children in that household?

Back

1.97

Front

A discrete random variable X has the probability distributions shown in the table. Find the value of k. (Remember that a valid probability distribution must add up to 1)

Back

1/12

Front

Determine which of the following distribution is NOT a probability distribution. (Remember that a valid probability distribution must add up to 1)
Options: A, B, C, D

Back

D

Front

Is this a probability distribution?

Back

No, the sum of p(x) does not equal 1.

Front

The table above shows a television station's advertisement sales. The distribution of sales for one 24-hour day is given. Solve for the mean. Round to the nearest hundredth.

Back

31.8

Front

The table above shows a television station's advertisement sales. The distribution of sales for one 24-hour day is given. Solve for the standard deviation. Round to the nearest hundredth.

Back

16.3