SOLUTION: I am supposed to add a sequence of numbers starting with one and going to number thirty. I have added them together and I got 465 as an answer. They want me to write a formula s

Algebra ->  Sequences-and-series -> SOLUTION: I am supposed to add a sequence of numbers starting with one and going to number thirty. I have added them together and I got 465 as an answer. They want me to write a formula s      Log On


   



Question 388210: I am supposed to add a sequence of numbers starting with one and going to number thirty. I have added them together and I got 465 as an answer. They want me to write a formula showing this. I don't know what to do next. I think it is something like 1+2+3...=30. but I am not sure.
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
1+2+3+4+5+...+30 = %2830%2F2%29%281%2B30%29+=+15%2A31+=+465.
This answer comes from the formula S_n+=+%28n%2F2%29%28a_1%2Ba_n%29, where
a_1 = 1st term of the sequence,
a_n = nth term of the sequence, and S_n = sum of the 1st to the nth terms.