Question

A paper is 80cm long and 30cm broad, the area of a paper is...
\[\begin{align}
  & A.2400c{{m}^{2}} \\
 & B.2400cm \\
 & C.3600c{{m}^{2}} \\
 & D.\text{None of these} \\
\end{align}\]

Answer 1

Hint: We know that a paper is in the form of a rectangle. We also know that its area is equal to the product of its length and breadth. So, if we have a rectangle of length (l) and breadth (b) then, its area is given by,
\[\text{Area = l }\times \text{ b sq}\text{.units}\]
In our question, we have been given these two dimensions, so we can directly substitute in the above formula and get the answer.

Complete step by step solution:
We have been given a paper 80cm long and 30cm broad, so we have to find its area. Let us draw the figure to understand how it looks.

We can see that the paper is in the form of a rectangle and its area is equal to the product of its length and breadth. Mathematically, it is represented as follows,
\[\text{Area of rectangle = l }\times \text{ b sq}\text{.units}\]
We have been given that l = 80cm and b = 30cm. Now, substituting these values, we get
\[\begin{align}
  & \text{Area = 80}\times \text{30} \\
 & \Rightarrow \text{2400c}{{\text{m}}^{\text{2}}} \\
\end{align}\]
Hence, we have got the area of the paper is equal to $\text{2400c}{{\text{m}}^{\text{2}}}$
Therefore, the correct option is A.

Note: In this question, it is very important that you choose the option correctly as you can make mistakes there, since the option A and B both are quite similar, the only difference is that their units are different. So, choose the option wisely.