The mean of 7 numbers is 68. Of them, 6 are 63, 62, 73, 57, 70, 76. What is the remaining number?
Answer and explanation
Correct answer: A.
- Step 1: Total of all numbers: . Step 2. Sum of the given numbers: . Remaining number: . **Answer: . Why not the others:** assumes the missing number equals the mean; adds the count to the answer; divides by the wrong count.
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