Question

an open cylinder box of hight 20 cm and diameter of base 21cm is to be made using a cardboard find the area of cardboard required to make the box

Answer 1

Answer:

1320 $cm^{2}$

Step-by-step explanation:

Step 1 : h= 20 cm

d = 21 cm

so r = d/2 = 21/2 = 10.5 cm

Step 2 : area of required cardboard = S.A. of cylinder

= $2\pi rh$

= 2 * 22/7 * 10.5 * 20

= 1320 $cm^{2}$