You roll two six-sided dice. What is the probability that the sum of the numbers will be a prime number?
Category: Math · Difficulty: expert
Hint: Count how many prime sums can be rolled.
Answer
5/12
Explanation
The sums that are prime are 3, 5, 7, 11, which occur in 15 of 36 total outcomes.
This is a expert math riddle — one of the harder riddles here. The answer is 5/12.
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