If the sum of 1 + 2 + 2 2 + ........ + 2 n - 1 is 255, find the value of n.

Common ratio = 2. Since, |r| 1 Hence, n = 8.

In a G.P., the ratio between the sum of first three terms and that of the first six terms is 125 : 152. Find its common ratio.

If the sum of 1 + 2 + 2² + …….. + 2^{n - 1} is 255, find the value of n.