Question

How much sheet of metal is required to make a closed rectangular box of length 1.5 m, bredth 1 m and height 2 m?

Answer 1

A closedr rectangular box means a cuboidal box. So to find the metal sheet required to make that box is same a sthe total surface area of that cuboidal box.

Now, we know that
TSA of the cuboid = 2 (lb + bh + hl)
=> TSA of the cuboid = 2 (1.5 x 1 + 1 x 2 + 2 x 1.5)
=> TSA of the cuboid = 2 (1.5 + 2 + 3)
=> TSA of the cuboid = 2 (4.5)
=> TSA of the cuboid = 9 <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> ${cm}^2$

Hence 9 <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> ${cm}^2$ of metal sheet will be required to make that box.