Question

What is the average of the first 200 terms of the series 1,-2,3,-4,5,-6,7,---e?

Answer 1

Average of the first 200 terms of the series 1,-2,3,-4,5,-6,7...

=1+(-2)+3+(-4)+...+199+(-200)/200

=(1-2)+(3-4)+(5-6)+...+(199-200)/200

=(-1)+(-1)+(-1)+...100times/200

=-100/200

=-0.5