The probability that it rains on any day in a town is . About how many rainy days are expected in days?
Answer and explanation
Correct answer: D. 30
- Step 1: Expected number probability number of trials.
- Step 2: .
Answer
30.
Why not the others: 3: This is a tenth of the correct answer, using . 170: This is the expected number of dry days. 60: This doubles the correct answer.
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