Question

Using properties of addition and multiplication, find the value of $756\times 428$.

Answer 1

$756\times 428$

$\Rightarrow (592+164)(592-164)$

$\Rightarrow {592}^2-{164}^2$

$\Rightarrow (600-8{)}^2-(150+14{)}^2$

$\Rightarrow (360000-9600+64)-(22500+4200+196)$

$\Rightarrow 350464-26896$

$\Rightarrow 323568$.