Answer: 1/3
Explanation:
the card is not being replaced, so it is a dependent event.
Event A: picking an odd number
There are 4 cards total, and 2 odd numbered cards.
P(A) = 2/4 = 1/2
Event B: picking an even number.
There are now three cards total, because the card from Event A was not replaced. There are two even numbered cards.
P(B) = 2/3
P(A+B) = P(A) x P(B)
P(A+B) = 1/2 x 2/3 = 2/6 = 1/3