## anonymous one year ago .

1. anonymous

how would that helpme? there is nothing about algebra there @whoperman28

2. anonymous

sort of..

3. anonymous

okay and what is n

4. anonymous

okay, so now what do we do

5. anonymous

wait where did the 5 come from?

6. UnkleRhaukus

The formula for the sum of a finite Arithmetic series is $S_n = \frac n2(s_0+s_n)$ where $$s_1$$ is the first term, $$s_n$$ is the last term, and $$m$$ is the number of terms

7. anonymous

okay

8. anonymous

now what?

9. anonymous

someone please its 2am im so tireddd

10. anonymous

omg please help wolf my back is killing me i never want to see this laptop ever again

11. wolf1728

Okay here it is explained a little easier. The sum of consecutive integers from 1 to 100 would be n*(n+1) /2 = 100 * 101 /2 = 5,050 Let's suppose you have to sum 11 to 100? We know 1 to 100 = 5,050 So, to sum 11 to 100 we would have to subtract sum of 1 to 10 10 * 11 /2= 110 / 2 =55 SO, sum of 11to 100 equals 5,050 MINUS 55 = 4,995

12. wolf1728

SO, you have to sum 5 through 11 using the formula? sum of 1 to 11 = 11 * 12 / 2 = 66 sum of 1 to 4 = 4 *5/2 = 10 66 - 10 = 56

13. anonymous

@wolf1728 so is that the entire anser? and that is simple lol??

14. anonymous

@wolf1728 ahhhhhhhhhhhhhhhhhhhhhhhhhhh

15. wolf1728

Yes that is it. As you probably know you could just as easily add up 5+ 6+ 7+ 8+ 9+ 10+ 11 using pencil and paper but I guess they just want you to get familiar with formulas.

16. anonymous

lol wow. okay thnk you