the sum of the first three terms of a G.P. is to the sum of first six terms as 125:152.Find the common ratio of the G.P.
S3 / S5 = 125 /152
a(1- r3) / 1-r / a(1- r5) / 1-r = 125 /152
1- r3 / 1- r6 = 125 /152
1- r3 / (1)2 - (r3 )2 = 125 /152
1- r3 / (1+ r3)(1- r3) = 125 /152
1 / 1+ r3 = 125 /152
152 = 125 + 125r3
125r3 = 27
r3 = 27 /152
r3 = (3/5)3
r=3/5