Question

You pick a card at random, put it back, and then pick another card at random.

6, 7, 8, 9.

What is the probability of picking a 9 and then picking a number greater than 7?

Write your answer as a percentage.

Answer 1

Answer:32%

Explanation:

Answer 2

12.5%

Explanation:

There are 4 cards to choose from in the beginning.

Pick 9 out of the 4.

p(9) = 1/4

You put the card back. Now there are again 4 cards.

There are 2 numbers greater than 7: 8 and 9.

p(8 or 9) = 2/4 = 1/2

p(9 then number greater than 7) = 1/4 × 1/2 = 1/8

1/8 = x/100

8x = 100

x = 100/8

x = 12.5%

Answer: 12.5%