Question

The surface area of a cuboid is $1300c{m}^2$, if its breadth is $10cm$ and height is $20cm$, find its length.

Answer 1

Surface area of a cuboid $=1300c{m}^2$
Breadth $=10cm$
Height $=20cm$
Let $l$ be the length of cuboid

We know that,
Surface area of cuboid $=2(lb+bh+hl)$
$1300=2(l\times 10+10\times 20+l\times 20)$
$650=30l+200$
$450=30l$
$l=\frac{450}{30}$
$l=15cm$
Hence, the length of cuboid is $15cm$