What is P(A|B) ? Express your answer as a fraction.

Question

Two six-sided dice are rolled, one after the other.

Let A be the event that the first die comes up as a 4.

Let B be the event that the sum the numbers from the two rolls is even.

Answer 1

if the first die comes up a 4 then the possibilities for the sums would be

4+1=5 odd

4+2=6 even

4+3=7 odd

4+4=8 even

4+5=9 odd

4+6=10 even

So 1/2 the outcomes will be even