What is the sum of the first five terms of a geometric series with ay = 20 and
r= 1/4?

Step-by-step explanation:

What is the sum of the first five terms of a geometric series with a1 = 20 and r= 1/4?

For a Geometric series, the sum S, is given by  

s=a_1 ((1-r^n)/(1-r))

a=20 ,      n=5,         r=1/4

s=20((1-〖(1/4)〗^5)/(1-1/4))=26 2/3

(23*2)-12=x     x=34

step-by-step explanation: