Question

Practice Set 9.1
Length, breadth and height of a cuboid shape box of medicine is 20cm, 12 cm and 10 cm
respectively. Find the surface area of vertical faces and total surface area of this box.
Total
Ath and height is 6 unit​

Answer 1

i.Surface area of vertical faces of the box

= 2(l + b) x h

= 2(20+ 12) x 10

= 2 x 32 x 10

= 640 sq.cm.

ii. Total surface area of the box

= 2 (lb + bh + lh)

= 2(20 x 12+ 12 x 10 + 20 x 10)

= 2(240 + 120 + 200)

= 2 x 560

= 1120 sq.cm.

∴ The surface area of vertical faces and total surface area of the box are 640 sq.cm, and 1120 sq.cm, respectively.