A table-top measures $ 2 \mathrm{~m} $ by $ 1 \mathrm{~m}\ 50 \mathrm{~cm} $. What is its area in square metres?

Given:  

A table-top measures $2\ m $ by $1\ m\ 50\ cm$.

To do: 

We have to find the area of the table-top in square meters.

Solution:

We know that,

The area of a rectangle with length '$l$' and breadth '$b$' is $l \times b$.

Since,

$1\ m=100\ cm$

This implies,

$1\ cm=\frac{1}{100}\ m$

Breadth $b =1\ m \ 50\ cm$

$=1\times\frac{50}{100}$

$=1.50\ m$

Therefore,

Length $l =2\ m$ and breadth $b =1.50\ m$

The area of the rectangle $ = 2\ m\times1.50\ m$

$=3\ m^2$

The area of the table-top in square meters is $3\ m^2$.