UPSC 2014 CDS II Math Paper

Remainder when 1235 is divided by 12=11
Remainder when 4523 is divided by 12=11
Remainder when 2451 is divided by12=3
∴Remainder when 1235×4523×2451 is divided by 12
Remainder when 11×11×3
= 363 is divisible by 12
=3