Question

Please help

Marcy plays a game with a spinner and a 6-sided number cube. The spinner is divided into 4 equal sections numbered 1 to 4. Marcy spins the spinner and rolls the number cube. She records both numbers. What is the probability that at least one of the numbers is a 4? Write out the sample space to help you

Answer 1

9/24 or 3/8

Explanation:

Spinner gives a 4.

Suppose the 4 shows up on the spinner.

There is a 1/4 chance of that happening.

Suppose the cube does not have a 4 on the top face. There is a 5/6 chance of that happening

Together the probability is 1/4 * 5/6 = 5/24

The cube gives a 4

The cube gives a four 1/6 of the time.

The spinner cannot give a 4, which happens 3/4 of the time.

Together the probability is 1/6 * 3/4 = 3/24

Both Cube and Spinner give a 4

The cube will give a four 1/6 of the time

The spinner gives a four 1/4 of the time.

1/6*1/4 = 1/24

Total

1/24 + 3/24 + 5/24 = 9/24 = 3/8

What happens to the rest?

The answer is neither gives a four.

Spinner 3/4

Die: 5/6

Combined amount = 3/4 * 5/6 = 15/24

There is a quick way to do this.

1 - no fours =

1 - 15/24 = 9/24