Explain the sum of geometric progression​

A geometric progression is a sequence in which any element after the first is obtained by multiplying the preceding element by a constant called the common ratio which is denoted by r.

For example, the sequence 1, 2, 4, 8, 16, 32… is a geometric sequence with a common ratio of r = 2.

When 1 is multiplied by 2 it results in 2. When 2 is multiplied by 2 it gives 4. Likewise, when 4 is multiplied by 2 we get 8 and so on.