Question

What is the approximate volume of a tree trunk if the trunk is 13 feet tall with a circumference of 4.5 feet?
A. 33.09 ft3
B. 21.17 ft3
C. 17.16 ft3
D. 27.14 ft3

Answer 1

What kind of shape do you think the tree trunk would have?

Answer 2

so you know that the circumference of a circle is 2pi*r ,so this mean that

4,5 = 2pi*r
4,5 = 2*3,14*r
4,5= 6,28*r

r = 4,5/6,28 = 0,716 feet

r = 0,716 feet

so than you can calculi area of base ,what will be pi*r^2

area of base = 3,14*(0,716)^2 = 3,14*0,512 = 1,607 feet^2

A = 1,607 feet ^2

Volume equal area of base time tall of the tree trunk

V = 1,607*13 = 20,891 feet^3

depend how was rounded these results - so from the above choices the B. is right sure