Solve the problem.
-Seven slips of paper marked with the numbers 1, 2, 3, 4, 5, 6, and 7 are placed in a box and mixed well. Two are drawn. What are the odds that the sum of the numbers on the two selected slips is not 6?
A) 9 to 1
B) 21 to 2
C) 19 to 1
D) 19 to 2

Question

Quizplus · Accepted Answer

The total number of ways to draw 2 slips out of 7 is 7C2 = (7*6)/(2*1) = 21. The combinations that sum to 6 are (1,5), (2,4), and (5,1), (4,2), which are 2 distinct pairs since order doesn't matter in this context. So, there are 21 - 2 = 19 combinations that do not sum to 6. The odds in favor are 19 successful outcomes to 2 not successful, or 19 to 2.

Solve the Problem. -Seven Slips of Paper Marked with the Numbers 1, 2