CA Foundation · Quantitative Aptitude · Sequence and Series
The sum of three numbers in AP is 27 and the sum of their squares is 293. What is the largest of the three numbers?
The largest number is 14. Taking the numbers as 9-d, 9, 9+d, the squares sum to 243 + 2d² = 293, so d = 5, giving 4, 9 and 14. Note that 14 is not among the listed options.
- A13Correct
- B11
- C15
- D17
Explanation
Let the numbers be 9-d, 9, 9+d. Sum of squares = 243 + 2d² = 293, so d² = 25 and d = 5. The numbers are 4, 9, 14, whose sum is 27 and squares 16+81+196 = 293. The largest is 14.
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