Numbers-7 (CAT-2002)

Number S is equal to the square of the sum of digits of a 2 digit number D. if the difference between S and D is 27, then D is:

(1)32   (2)64   (3)54   (4)52

Solution follows here:

Solution:

Best approach for this problem is going from the given options:

Option(1); D=32 => S = (3+2)² = 25;  D-S = 7 ≠ 27 => option is wrong

Option(2); D=64 => S = (6+4)² = 100;  S-D = 36 ≠ 27 => option is wrong        

Option(3); D=54 => S = (5+4)² = 81;  S-D = 27 => option is correct

Answer (3)