Question

calculate 1-2+3-4+5-6+........+179-180​

Answer 1

Answer:

90

Step-by-step explanation:

1-2=1

3-4=1

5-6=1

then

180/2=90

I hope this helpful

Answer 2

S =   1 - 2 + 3 - 4 + 5 - 6 + ___ + 179 - 180

+   S =       1 - 2 + 3 -  4 + 5 - 6 + ___ + 179 - 180

----------------------------------------------------------------

2S =           1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - ___ - 1 - 1 - 1 - 180

2S = -180

S =   $\frac{-180}{2}$

S = -90