The height of a joker cap is 21 CM and its slant it is 28 CM find the surface area of 10 such caps

Answer 1

SA=(pi)rl =(pi)lsqr(28^2-21^2)

=pi(28)sqr(343)

= about 28(18.52)pi

= about 518.57pi cm^2

= about 1,629.13 cm^2

10 hats area= about 16,291.3 cm^2

if joker's cap=jester's cap or =dunce hat

= open cone

l=28 h=21

r=radius=sqr343

r^2=l^2-h^2=28^2-21^2 = 343