A pair of fair 6 -sided dice is rolled n times. What is the least value of n such that the probability that the sum of the numbers face up on a roll equals 7 at least once is greater than \dfrac{1}{2} ?

**Answer Choices**

A. 2

B. 3

C. 4

D. 5

E. 6

A pair of fair 6 -sided dice is rolled n times. What is the least value of n such that the probability that the sum of the numbers face up on a roll equals 7 at least once is greater than \dfrac{1}{2} ?

**Answer Choices**

A. 2

B. 3

C. 4

D. 5

E. 6