Answer:
22.5 cm^2
Step-by-step explanation:
Amount of paper is going to be measured in area, so we want the surface area of the cone. Since it is a cub it doesn't have a base, so we don't need to count it.
Area of the cone without the base, or what is called the lateral area is pi*r*s where r is the radius and s is the slant height. and of course radius is d/2 where d is the diameter. so let's plug it in. We know diameter is 6 and slant height is 7.5
SA = pi * r * s
SA = pi * d/2 * s
SA = pi * 6/2 * 7.5
SA = 22.5 cm^2
So you will need 22.5 square centimeters of paper.
Are these two separate questions?
Assuming the shape is a piece of a circle, you can determine the ratio of the shape to a full circle. A full circle will have 360 degree but this shape is only 40 degree. Then the ratio would be: 40/360= 1/9 full circle.
Then, using the circle area formula, the area of the 1/9 circle would be:
full circle area= pi * r^2
full circle area= 22/7 * 6^2
full circle area= 792/7
1/9 full circle area= 792/7*9= 88/7 = 12.57
9-5=4 Therefore f=4
Hope this helps
