Question

Using mental math, the value of $3,700+2,300=$

Answer 1

$\because 3700=4000-300$
And $2300=2000+300$
$\Rightarrow 3700+2300=4000-300+2000+300$
$\Rightarrow 3700+2300=4000+2000+300-300$
$\Rightarrow 3700+2300=6000$