Week 3: Probability

Which of the following events relate to the classical probability? Choose all that apply.

• A baseball player gets a hit in 30 out of 100 times at bat. The probability is 0.3 that he gets a hit in his next at bat.

• A seven-member committee of students is formed to study environmental issues. What is the likelihood that any one of the seven is randomly chosen as the spokesperson?

• Estimating the likelihood the New England Patriots will play in the Super Bowl next year.

• Stephen Curry of the Golden State Warriors made 363 out of 400 free throw attempts during the 2015–16 NBA season. The likelihood of him making his next free throw attempt is 0.908.

Suppose P(A) = 0.40 and P(B | A) = 0.30. What is the joint probability of A and B  ( $P\left(A\cap B\right)$ )? 

A local bank reports that 80% of its customers maintain a checking account, 60% have a savings account, and 50% have both. If a customer is chosen at random, what is the probability the customer has either a checking or a savings account?

• 1

• 0.9

• 0.3

• 0.5

Each salesperson at Puchett, Sheets, and Hogan Insurance Agency is rated either below average, average, or above average with respect to sales ability. Each salesperson also is rated with respect to his or her potential for advancement— either fair, good, or excellent. These traits for the 500 salespeople were cross- classified into the following table.

What is the probability a salesperson selected at random will have above average sales ability and excellent potential for advancement?

A pollster randomly selected 4 of 10 available people. How many different groups of 4 are possible?

• 210

• 40

• 70

• 5040

Sam Snead’s restaurant in Conway, South Carolina, offers an early bird special from 4–6 p.m. each weekday evening. If each patron selects a Starter Selection (4 options), an Entrée (8 options), and a Dessert (3 options), how many different meals are possible?

• 12

• 15

• 96

• 124

Solve the following: 
 $\ _7P_4\ =\ ?$