1.  Which one will replace the question mark ?

A. 660
B. 670
C. 610
D. 690

Answer: Option D

Explanation:

(1)2 + (5)2 + (4)2 + (3)2 = 51 x 10 = 510

and (3)2 + (4)2 + (6)2 + (2)2 = 65 x 10 = 650

Similarly (0)2 + (1)2 + (2)2 + (8)2 = 69 x 10 = 690.