Question

If the volume of a cuboid is $448{cm}^3$ and its height is $7$ cm and the base is a square.find (i)the side of the square base (ii) surface area of the cuboid.

Answer 1

volume of cuboid $=l\times b\times h=448c{m}^3$

$=l\times b\times 7=448c{m}^3$

$=l\times b=64c{m}^2$

but base is square

$\therefore l=b$

$\therefore l^2=64c{m}^2$

$\Rightarrow l=b=8cm$

surface area $=2(lb+lh+bh)$

$=2(8\times 8+8\times 7+8\times 7)$

$=2(64+56+56)$

$=352$$c{m}^2$