Question

A toy is in the form of a right circular cylinder with a right circular cone fixed above it.The diameter and the height of cylindrical part of the toy are126 cm and 5 cm respectively. The total height of the toy is 21 cm. Find the total surface area of the toy.

Answer 1

Hi ,

i ) dimensions of the cylinder:

Diameter of the base = d = 126cm

Radius = d/2

r = 126/2 = 63cm

Height = h = 5cm

ii) Dimensions of the cone:

radius = r = 63 cm

Height of the cone

= total height of the toy - h

= 21 - 5

H = 16 cm

Slant height = l

l^2 = r^2 + h^2

= 16^2 + 63^2

= 3969 + 256

= 4225

l = sqrt(4225)

l = 65 cm

iii ) Total surface area of the toy

= lateral surface area of the cylinder

+ base area of the cylinder +

curved surface area of the cone

= 2× pi×rh + pi × r^2 + pi × r l

= pi × r [ 2h + r + l ]

= 22/7 × 63 [ 2× 5 + 63 + 65 ]

= 22 × 9 ( 10 + 63 + 65 )

= 198 × 138

= 27324 Square cm

Therefore ,

Total surface area of the toy = 27324

Square cm

I hope this helps you.

***

Answer 2

hope I will help you

OM NAMAH SHIVAAY