UPSC CDS 2 2020 Math Paper

Concept Used:
Divisibility rule of 4 :
A number is divisible by 4 if its last two digits are divisible by 4
Calculations :
Remainder when 15 divided by 4=1
Remainder when 25 or 32 divided by 4=0
Remainder when 35 or 243 divided by 4=3
Remainder when 45 or 1024 divided by 4=0
Remainder when 55 or 3125 divided by 4=1
Remainder =1+3+1=5
Remainder when 5 divided by 4=1