Question

A gift containing cylinder surmounted by cone is to be wrapped. What is the surface area to be wrapped if the cylinder of 10 cm height and 3.5 cm radius and cone has slant height of 7 cm ?

• A. $235.5{\text{cm}}^2$
• B. $200.5{\text{cm}}^2$
• C. $335.5{\text{cm}}^2$
• D. $300.5{\text{cm}}^2$

Answer 1

The correct option is C $335.5{\text{cm}}^2$

Given,
Solid combination: Cylinder+Cone
Radius of cone and cylinder $r=3.5\text{cm}$
Height of cylinder, $h=10\text{cm}$
Slant height of cone, $l=7\text{cm}$

Surface area of gift wrap
= CSA of cylinder + Base area of cylinder + CSA of cone
$=2\pi rh+\pi r^2+\pi rl=\pi r(2h+r+l)=\frac{22}{7}\times 3.5(2\times 10+3.5+7)=22\times 0.5(20+10.5)=11\times 30.5=335.5{\text{cm}}^2$

The area of gift wrap required is $335.5{\text{cm}}^2$