a balloon has a circumference of 22inch. use the circumference to approximate the surface area of the balloon to the nearest square inch.

Question

a. 154 inch^2
b.616in^2
c.1521in^2
d.484in^2

Answer 1

To find the surface area of the balloon, we will use the formula for the surface area of a sphere:

Surface Area = 4πr^2

Given that the circumference of the balloon is 22 inches, we can use the formula for circumference to find the radius:

Circumference = 2πr
22 = 2πr
r = 22/(2π) = 11/π ≈ 3.5 inches

Now, we can plug the radius into the surface area formula:

Surface Area = 4π(3.5)^2
Surface Area ≈ 4π(12.25)
Surface Area ≈ 49π
Surface Area ≈ 153.94 in^2

Rounded to the nearest square inch, the surface area of the balloon is approximately 154 in^2.

Therefore, the closest answer choice is:

a. 154 inch^2