Question

Total surface area of a box of cuboid shape is 500 sq.unit. Its breadth and height is 6 unit and 5 unit respectively. What is the length of that box?

Answer 1

Given: For cuboid shape box, 

breadth (b) = 6 unit, height (h) = 5 unit Total surface area = 500 sq. unit.

To find: Length of the box (l) 

Solution:

Total surface area of the box = 2 (lb + bh + lh) 

∴ 500 = 2 (6l + 6 x 5 + 5l)

∴ \(\frac{500}{2}\) = (11l + 30) 

∴ 250 = 11l + 30 

∴ 250 – 30= 11l 

∴ 220 = 11l 

∴ 220 = l 

∴\(\frac{220}{11}\) = l 

∴ l = 20 units 

∴ The length of the box is 20 units.