There is a stack of

8

cards, each given a different number from

1

to

8

. Suppose we select a card randomly from the stack, replace it, and then randomly select another card. What is the probability that the first card is an odd number and the second card is greater than

6

?

Probability you'd pick an odd number:

1 2 3 4 5 6 7 8

Odd numbers: 1 3 5 7

There are 4/8 odd numbers so probability is 4/8 first pick.

Card is put back so you still have 8 cards. Probability greater than 6:

7 and 8 are greater than 6, so that's 2 out of 8 cards. Probability: 2/8

Multiply both probabilities together: 4/8 x 2/8 = 8/64 = 1/8

4/8 odd numbers you will pick.