Two fair dice are thrown. Find the probability that the sum is .
Answer and explanation
Correct answer: A.
- Step 1: There are equally likely outcomes.
- Step 2: The pairs giving a sum of number , so .
Answer
.
Why not the others: is what you get if you count only one favourable outcome. is what you get if you use outcomes instead of . is what you get if you count one outcome too many.
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