Question

Find the sum of 8 terms of the Arithmetic series: 3,6,9,......

Answer 1

Explanation:

below

Answer 2

Explanation:

so write 8 terms.. By observation we know this series just add 3 for each element in the series...

3,6,9,12,15,18,21,24

now we have 8 terms, just add those

3+6+9+12+15+18+21+24= 108

I used my calculator :P