Question

What is the sum of the arithmetic sequence 174, 168, 162 …, if there are 31 terms? 2,604 2,635 2,666 2,697

Answer 1

174 + [174 - 6(1)] + [174 - 6(2)] + [174 - 6(3)] + . . . + [174 - 6(30)]

= (174)(31) - 6(1 + 2 + 3 + . . . + 30)

= (174)(31) - (6)(30)(31)/2

That last part is derived from:

1 + 2 + 3 + . . . + n = n(n + 1)/2

Answer 2

So, all you have to do is simplify:

(174)(31) - (6)(30)(31)/2

Answer 3

i.....ohhh

Answer 4

thanks abunch bro

Answer 5

uw! Good luck to you in all of your studies and thx for the recognition! @XAY_____

Answer 6

thnx again

Answer 7

Anytime!