Question

List the sample space for rolling two dice and finding the sum of the numbers. How many 8's are there in the sample space? [Assume that rolling a 3 and a 5 is the same as rolling a 5 and a 3.]

A) 2
B) 3
C) 4
D) 5

Answer 1

The attached figure shows the sample space. The summation of the numbers in brackets forms the required results.

Looking at the sample space, the numbers whose sum is 8 are:

(6,2), (5,3), (4,4), (3,5), (2,6)

But, based on the condition that (5,3) is the same as (3,5), it follows that (6,2) is the same as (2,6).

Therefore, there are three 8's as shown below:
(6 and 2), (5 and 3) and (4 and 4). Therefore, the correct answer is B.