Select the option that is related to the third number in the same way as the second number is related to the first number and the sixth number is related to the fifth number.
17 : 255 :: 21 : ? :: 24 : 528
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 399.
17 : 255 → 172 - (17 × 2) = 289 - 34 = 255
24 : 528 → 142 - (24 × 2) = 576 - 48 = 528
Similarly, 21 : ? → 212 - (21 × 2) = 441 - 42 = 399