Question

In each of the following questions a number series is given. After the series a number is given followed by (A), (B), (C), (D) and (E). Complete the series starting with the number given following the sequence of the given series. Then, answer the question given below each:
434, 353, 417, 368, 404, 379,
108 (A), (B), (C), (D), (E)
Which of the following numbers will come in place of (E)?

• A. 27
• B. 91
• C. 42
• D. 53
• E. 78

Answer 1

The correct option is D 53

434 - 353 = $9^2$
353 - 417 = $8^2$
417 - 368 = $7^2$
368 - 404 = $6^2$
404 - 379 = $5^2$
$\therefore$ 108 - (A) = $9^2\Rightarrow$ (A) = 108 - 81 = 27
27 - (B) = -$8^2\Rightarrow$ (B) = 27 + 64 = 91
91 - (C) = $7^2\Rightarrow$ (C) = 91 - 49 = 42
42 - (D) = -$6^2\Rightarrow$ (D) = 42 + 36 = 78
78 - (E) $5^2\Rightarrow$ (E) = 78 - 25 = 53.