Question

The lid of a rectangular box of sides $40\mathrm{cm}$ by $10\mathrm{cm}$ is sealed all around with tape. What is the length of the tape required?

Answer 1

Solution.

The length of the required tape is equal to the perimeter of the rectangle.

We know that,

$$\begin{gathered} \mathrm{Perimeter}\mathrm{of}\mathrm{rectangle}=2(\mathrm{Length}+\mathrm{Breadth}) \\ \Rightarrow =2(40+10) \\ \Rightarrow =2\times 50 \\ \Rightarrow =100\mathrm{cm} \end{gathered}$$

Hence, the length of the required tape is $100\mathrm{cm}$.