Question

Solve the problem using direct multiplication method to find the square of $310$.

Answer 1

We can write ${310}^2=(300+10{)}^2$

Using $(a+b{)}^2=a(a+b)+b(a+b)$
Here $a=300,b=10$
Therefore, ${310}^2=300(300+10)+10(300+10)$
$=$ ${300}^2+3000+3000+{10}^2$
$=90000+6000+100$
$=96100$