Question

The first number in a series of 100 numbers is – 82. The last is 215. Find the sum of those numbers.

Answer 1

Answer:

a=-82

n =100

an=215

a+(n-1)d =215

-82+(100-1)d=215

-82+99d =215

99d =215+82

99d =297

d = 3

sn=n/2(2a+(n-1)d)

=50{-164+297}

=50(133)

=6650