Question

The square of a number is $\mathrm{2.25.}$ Find the number.

Answer 1

The square of a number is $\mathrm{2.25.}$
Let the number be $x.$

$\therefore x^2=2.25\Rightarrow x=\sqrt{2.25}\Rightarrow x=\sqrt{\frac{225}{100}}\Rightarrow x=\frac{\sqrt{225}}{\sqrt{100}}\Rightarrow x=\frac{\sqrt{{15}^2}}{\sqrt{{10}^2}}\Rightarrow x=\frac{15}{10}\Rightarrow x=1.5$

$\therefore$ The required number is $\mathrm{1.5.}$