Answer:
128
Step-by-step explanation:
As common ratio is 1/4 ; let the first four terms of the geometric series be :
x , 1 / 4 .x , (1 / 4)2 .x , (1 / 4)3 .x or
x , x / 4 , x / 16 and x / 64
Now there sum is 170
, hence
x + x / 4 + x / 16 + x / 64 = 170 or
(64a + 16a + 4a + a ) / 64 = 170 or
85a / 64 = 170
a = 128
Hence first first term of the series is
128
