Question

There is a remainder of 3 when a number is divided by 6. What will be the remainder if the square of the same number is divided by 6?

• A. 1
• B. 0
• C. 3
• D. 2

Answer 1

Answer: (C)

3

Let the no. be ${}^{\prime }{x}^{\prime }$ $\Rightarrow x=6q+3$

$x^2=(6q+3{)}^2=36q^2+36q+9$

Divide $x^2$ by $6$

we get $x^2=6(6q^2+6q+1)+3$

Hence the remainder is $3$