A closed rectangular box has inner dimensions 90 cm by 80 cm by 70 cm. Calculate its capacity and the

area of tin-foil needed to line its inner surface.

Question

A closed rectangular box has inner dimensions 90 cm by 80 cm by 70 cm Calculate its capacity and the area of tinfoil needed to line its inner surface

Accepted Answer

It is given that

Inner length of rectangular box = 90 cm

Inner breadth of rectangular box = 80 cm

Inner height of rectangular box = 70 cm

We know that

Capacity of rectangular box = volume of rectangular box = l × b × h

Substituting the values

= 90 × 80 × 70

$=504000 \mathrm{cm}^{3}$

Here

Required area of tin foil = 2 (lb + bh + lh)

Substituting the values

= 2 (90 × 80 + 80 × 70 + 90 × 70)

By further calculation

= 2 (7200 + 5600 + 6300)

So we get

= 2 × 19100

$=38200 \mathrm{cm}^{2}$

ML Aggarwal Solutions Class 9 Mathematics Solutions for Mensuration Exercise 16.4 in Chapter 16 - Mensuration