Answer:
C. -5
Step-by-step explanation:
20 x 3 = 60
5 x 1 = 5
60 - 5 = 55
Let the original volume be pi *r^2* h where r = radius and h = height.
The new volume will be pi *(2/5 r)^2 * 4h = pi*4/25 r^2 4h
pi*4/25r^2 * 4h / pi r^2 h = 4/25 * 4 = 16/25
The volume has been reduced by factor of 16/25.
The common ratio is 1/2 and the first term is 32
f(x)=A1×(common ratio)^x-1
f(x)=32×(1/2)^x-1
Your answer is D.