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Question

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anonymous · Answer

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

anonymous · Answer

sort of..

anonymous · Answer

okay and what is n

anonymous · Answer

okay, so now what do we do

anonymous · Answer

wait where did the 5 come from?

unklerhaukus · Answer

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

anonymous · Answer

okay

anonymous · Answer

now what?

anonymous · Answer

someone please its 2am im so tireddd

anonymous · Answer

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

wolf1728 · Answer

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

wolf1728 · Answer

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

anonymous · Answer

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

anonymous · Answer

@wolf1728 ahhhhhhhhhhhhhhhhhhhhhhhhhhh

wolf1728 · Answer

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.

anonymous · Answer

lol wow. okay thnk you