Asked by Maya
Two dice are rolled. Find the probability that an even number is rolled on one die and an odd number is rolled on the second die.
Answers
Answered by
Reiny
You could have EO, or OE
prob(EO) = (/12)(1/2) = 1/4
prob(OE) = (/12)(1/2) = 1/4
so prob of one even one odd = 1/4 + 1/4 = 1/2
Another way:
make a chart with DIE1 on top and DIE2 on the side.
there will be 36 outcomes, 18 even sums and 18 odd sums.
(notice that the sum of an even + odd = odd, but the sum of either two evens or two odds is even)
so prob = 18/36 = 1/2
prob(EO) = (/12)(1/2) = 1/4
prob(OE) = (/12)(1/2) = 1/4
so prob of one even one odd = 1/4 + 1/4 = 1/2
Another way:
make a chart with DIE1 on top and DIE2 on the side.
there will be 36 outcomes, 18 even sums and 18 odd sums.
(notice that the sum of an even + odd = odd, but the sum of either two evens or two odds is even)
so prob = 18/36 = 1/2