Question

Please Help!!!

What is the sum of the first five terms of the series 7 + 12 + 17 + ... ?

A. 85

B. 51

C. 60

Answer 1

we meet again !...

It's an arithmetic series.
The sum of the first n terms of an arithmetic series:




The sum of the first five terms is 85.

Answer 2

There are only 5 numbers, so figure out what they are and add them.
Notice that each term is 5 more than the previous one, so add 5 to each term to find out the next term.

7 + 12 + 17 + 22 + 27 = 85

Answer: A. 85