What is the probability that the sum of two standard six-sided dice is 7?

• A. 1/6
• B. 1/36
• C. 5/36
• D. 1/3

Answer: (A)

Think about counting outcomes. When you roll two standard dice, there are 6 choices for the first die and 6 for the second, giving 36 equally likely ordered results.

For the sum to be 7, the valid ordered pairs are: (1,6), (2,5), (3,4) and their reverses (4,3), (5,2), (6,1). That makes six favorable outcomes.

So the probability is 6 favorable over 36 total, which simplifies to 1/6. This aligns with the idea that 7 is the most common sum with two dice because it has the most combination options.

The other numbers would imply fewer or more favorable outcomes than actually exist (1/36 would be one specific pair; 5/36 would be five pairs; 1/3 would be twelve pairs), which isn’t correct for the sum of 7.