Question

A bag contains eight yellow marbles, nine green marbles, three purple marbles, and five red marbles. Two marbles are chosen from the bag. What expression would give the probability that one marble is yellow and the other marble is red?

- 30%
- 40%
- 50%
- 60%

Answer 1

2/15 = 13 1/3 %

Explanation:

eight yellow marbles, nine green marbles, three purple marbles, and five red marbles = 25

P(yellow) = yellow/ total =8/25

Keep

7 yellow marbles, nine green marbles, three purple marbles, and five red marbles = 24

P(red) = red/total =5/24

P(yellow then red) = 8/25 * 5/24 = 1/15

Then we have (red, yellow) =

P(red) = red/ total =5/25 = 1/5

Keep

8 yellow marbles, nine green marbles, three purple marbles, and four red marbles = 24

P(yellow) = yellow/total =8/24 = 1/3

P(red, yellow) = 1/5*1/3 = 1/15

Add them together

1/15 + 1/15 = 2/15 =