The mean of five numbers is 12. When a sixth number is added, the mean becomes 14. What is the sixth number?
Answer and explanation
Correct answer: A. 24
- Step 1: Total of five numbers = 5 x 12 = 60. Step 2. Total of six numbers = 6 x 14 = 84. Step 3. Sixth number = 84 - 60 = 24. Answer: 24. Why not the others: 14: That is the new mean, not the new number. 26: That does not raise the total from 60 to 84. 12: That would leave the mean unchanged.
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