(Q13).A self help group wants to manufacture joker’s caps (conical caps) of 3 cm radius and 4 cm height. If the available colour paper sheet is 1000 cm2, then how many caps can be manufactured from that paper sheet?

4 cm3 cm

Radius of the cap (conical cap) (r) = cm

Height of the cap (h) = cm

Slant height l = √(r2 + h2)

(by Pythagoras theorem)

= √(2 + 2)

= √(+)

= √

= cm

C.S.A. of the cap = πrl

=
× ×

≃ cm2

Number of caps that can be made out of 1000 cm 2 =
1000
47.17
 ≃

∴ Number of caps = .