Five numbers have a mean of 12. When one of them, 20, is removed, what is the mean of the remaining four?
Answer and explanation
Correct answer: C. 10
- Step 1: The sum is 5 x 12 = 60.
- Step 2: Without 20 the sum is 40, and the mean of four numbers is 40 / 4 = 10.
Answer
10.
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