Select the option that is related to the fourth term in the same way as the first term is related to the second term and the fifth term is related to the sixth term.
5 : 21 :: ? : 252 :: 27 : 725
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 16.
Logic : (First Number )2 - 4 = Second Number
5 : 21
(5)2 - 4 = 25 - 4 = 21
27 : 725
(27)2 - 4 = 729 - 4 = 725
Similarly,
? : 252
(a)2 - 4 = 252
a = 252 + 4 = √256
a = 16
Hence ,16 is the correct answer.