Question

What is the square of the number $124$ using direct multiplication method?

Answer 1

We can write $124$ as $120+4$

So, we need to find $(120+4{)}^2$

Using $(a+b{)}^2=a(a+b)+b(a+b)$

Here $a=120,b=4$

Therefore, $(120+4{)}^2=120(120+4)+4(120+4)$

$=14400+480+480+16$

$=14400+960+16$

$=15376$