Quantitative Aptitude • Ratio, Average & MixtureMedium
The average of 8 numbers is 38. When one more number is added, the average becomes 41. What is the number added?
A. 65✓ Correct Answer
B. 24
C. 41
D. 44
💡 Solution & Explanation
Total of the 8 numbers = 8 × 38 = 304. Total of all 9 numbers = 9 × 41 = 369. The new number is the difference: 369 − 304 = 65. Shortcut: new number = new average + (old count × rise in average) = 41 + 8 × 3 = 65.
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