MateusLima30 wrote:
Hi guys! This question appeared on the Cracking the GRE 2019 premium version from Princeton Review. The book has a graphical explanation that did not convince me. Coud anyone provide me an insight on this?
When a pair of six-sided dice, each with faces numbered 1 to 6, is rolled once, what is the probability that the result is either a 3 and a 4 or a 5 and a prime number?
A pair of dice will have 6*6 or 36 ways.
you can get a 3 and 4 in two ways (3,4) or (4,3)
5 and a prime number ; (2,5) or (5,2) or (5,3) or (3,5) or (5,5)
total 7 ways...
Probability = 7/36