the average of first four numbers in a GP is 140. find the ratio.
Can't tell, without knowing more. For example, with a ratio of 2, we can have
37 1/3
74 2/3
149 1/3
298 2/3
sum = 560
avg = 140
with a ratio of 3, we have
14
42
126
378
with a ratio of sqrt(pi)=1.772 we have
48.769
86.441
153.213
271.562