Question

The area of the cardboard needed to make a box of size $25cm\times 15cm\times 8cm$ will be

(a) $390c{m}^2$

(b) $1390c{m}^2$

(c) $2780c{m}^2$

(d) $1000c{m}^2$

Answer 1

Size of box =25 cm, 15 cm, 8 cm

$\therefore$ Surface area =(lb+bh+hl)

$=2(25\times 15+15\times 8+8\times 25)c{m}^2$

$=2(375+120+200)c{m}^2=2\left(695\right)=1390c{m}^2$