The sum of the infinite geometric series 30 - 6 + 6/5 - 6/25 ..

a. 24
b. 30
c. 36
d. 25

isnt it 30?

S = a + ar + ar^2 + ar^3 + . . . = a / (1-r) , for |r| < 1

Here we have a = 30, r = -1/5

S = 30 / (1+1/5) = 30 / (6/5) = 30 * 5/6 = 25

Mαthmφm

the sum of and infinite g.p is given as a(1-r)
here r=-6/30=-1/5
and a=30
30(1-(-1/5))
30(1+1/5)
30(6/5)
36 is the answer

25.
My calculator gave me the answer.

I think its 25

idk