Question

The first term of a geometric series is 3, and the sun of the first term and the second term is 15 what is the sum of the first six terms

Answer 1

To solve this problem you must apply the proccedure shown below:
 1. You have the following information given in the problem above:
 - The first term of a geometric series is 3.
 - The sum of the first term and the second term is 15.
 2. Keeping this on mind, you must find the common ratio, as following:
 $3+3r=15 \\ 3r=12 \\ r=4$
 3. Now, multiply each term by the common ratio, and you will obtain:
 $3,12,48,192,768,3072$
 4. The sum of the first six terms is:
 $3+12+48+192+768+3072=4095$
 The answer is: $4095$