what is the sum of the finite arithmetic series?
(-10)+0+10+20+....+130

Question

what is the sum of the finite arithmetic series? 
(-10)+0+10+20+....+130

amistre64 · Answer

n(first + last)
-----------
        2

amistre64 · Answer

in other words we can know 2 times the sum better, then divide it in half

anonymous · Answer

The answer choices are 
900
1,000
950
955

aum · Answer

Can you figure out how many terms are in the sequence without using any formula?

amistre64 · Answer

what does the formula determine as an answer then?

amistre64 · Answer

icame up with at least 3 different number of terms in my head alone lol

amistre64 · Answer

A =   -10 +    0   + ...+130
+A = 130 + 120 + ... - 10
------------------------
2A = 120 + 120 + .... + 120,  n times

therefore A = 120n/2

anonymous · Answer

im not quite sure which one it is...

aum · Answer

10, 20   2 terms
10, 20, 30   3 terms
10, 20, 30, ...., 130  ? terms    

then include the first two terms.

anonymous · Answer

is it 900?

aum · Answer

Yes.