Question

Estimate the square root of $140$ to the nearest integer.

Answer 1

We know that ${11}^2=121and{12}^2=144$
So, $\sqrt{140}$ will lie between $\sqrt{121}and\sqrt{144}$ i.e. lie between $11and12$.
Now $140-121=19$
and $144-140=4$.
So the square root will be close to $\sqrt{144}$.
The approximate value of $\sqrt{140}$ is $12$.