Question

Cards labeled 5, 6, 7, 8, and 9 are in a stack. A card is drawn and not replaced. Then, a second card is drawn at random. Find the probability of drawing an even number first, then an odd number second.

Answer 1

3/10

Explanation:

Answer 2

Answer: 3/10

Work Shown:

A = first card is even

B = second card is odd

P(A) = 2/5 since there are two even cards out of five total

P(B given A) = 3/4 because we have 3 odd cards out of 5-1 = 4 left over total; this is when the first card is not replaced or put back.

P(A and B) = P(A)*P(B given A)

P(A and B) = (2/5)*(3/4)

P(A and B) = (2*3)/(5*4)

P(A and B) = (2*3)/(5*2*2)

P(A and B) = (3)/(5*2)

P(A and B) = 3/10