Question

What is the sum of the geometric series 20 + 21 + 22 + 23 + 24 + … + 29?

Answer 1

There are no answer is right !

Answer 2

Answer:

The answer is a) 1,023

Step-by-step explanation:

A geometric series is a series with a constant ratio between successive terms. So, the given series must be in the exponential form.

$2^{0}+2^{1}+2^{2}+2^{3}+2^{4}+2^{5}+2^{6}+2^{7}+2^{8}+2^{9}$

We have been asked about the sum of the geometric series :

$1+2+8+16+32+64+128+256+512$

Sum = 1023

Hence, option A is the answer.

If Solving the series as it is given:

The given series : 20+21+22+23+....+29 is an arithmetic series.

Its sum is : $\frac{10(20+29)}{2}=245$

I have solved the question both ways. Both the answers are right with respect to the series name.