Question

The surface area of a cuboid is 1300 cm². If its breadth is 10 cm and height is 20 cm², find its length.

Answer 1

Let, l → Length of the cuboid

Breadth of the cuboid (b) = 10 cm

Height of the cuboid (h) = 20 cm

Surface area of the cuboid (A) = 1300 cm²

We have to find the length of the cuboid

We know that,

     A = 2 (lb + bh + hl)

1300 = 2(10l + 10 × 20 + 20l)

1300 = 2 (200 + 30l)

1300 = 400 + 60l

l =`(1300-400)/60`

 `=900/60`

  = 15 cm 

Length of the cuboid is 15 cm  .