Question

A balloon has a circumference of 22in. Use the circumference to approximate the surface area of the balloon to the nearset square inch.
possible answers;
154in^2
616in^2
1,521in^2
484in^2

Find the volume of the square pyramid.Round to nearest tenth if necessary.
The pyramid has a base of 24ft. and height of 15ft.
possible answers;
5,184ft^3
1,728ft^3
192ft^3
2,592ft^3

These are the only two problems I haven't been able to figure out. Would someone please help?

Answer 1

Ibelieve the 2nd one is 1,728ft^3, but I do not how to do the balloon.

Answer 2

c = 2pi*r, so r=c/2pi = 11/pi
a = 4pi*r^2 = 4pi(121/pi^2) = 484/pi = 154


v = 1/3 Bh = 1/3 (24^2)(15) = 2880

Answer 3

Is this right