Clinton and Stacy want to buy a trampoline for their kids. They are considering two trampolines.
Trampoline A has a diameter of 14 feet.
Trampoline B has a diameter of 20 feet.
Approximately how much greater, in square feet and rounded to the nearest hundredth, is the area of Trampoline B than the area of Trampoline A?
Use 3.14 for
.
Responses
A 640.56 ft2
B 18.84 ft2
C 241.86 ft2
D 160.14 ft2
To find the area of a circle, you use the formula A = πr^2, where r is the radius of the circle. Since the diameter is given, you must divide the diameter by 2 to get the radius.
For Trampoline A:
Radius of Trampoline A = 14 ft / 2 = 7 ft
Area of Trampoline A = π * (7 ft)^2 = 3.14 * 49 = 153.86 ft^2
For Trampoline B:
Radius of Trampoline B = 20 ft / 2 = 10 ft
Area of Trampoline B = π * (10 ft)^2 = 3.14 * 100 = 314 ft^2
To find the difference in area:
Area of Trampoline B - Area of Trampoline A = 314 ft^2 - 153.86 ft^2 ≈ 160.14 ft^2
Therefore, the area of Trampoline B is approximately 160.14 square feet greater than the area of Trampoline A.
The closest answer choice is D: 160.14 ft2.