Answer: B) 66.7%
Step-by-step explanation:
We know that, Number of outcomes on a fair die = 6
When we throw two dice , the total number of possible outcomes =
(By Fundamental counting principle)
The outcomes having either a 1 or a 6 = (1 , 1) (1 ,2) , (1,3) , (1,4) , (1,5) , (1,6)
(6, 1) (6 ,2) , (6,3) , (6,4) , (6,5) , (6,6)
i.e. Total 12 outcomes have either a 1 or a 6 .
So , the number of outcomes do not have either a 1 or a 6 = 36-12=24
i.e. favorable outcomes = 24
Now , the probability that you won't roll a 1 or a 6 on either die would become

In percent = 
Hence, the probability that you won't roll a 1 or a 6 on either die= 66.7%
Therefore , the correct answer is B) 66.7% .