Solve : 1000-999+998-997+... +4-3+2-1

Answer 1

divide it up into pairs.
each pair adds up to 1.
There are 500 pairs, so the sum is 500.

Answer 2

the answer is 500,500

Answer 3

Evaluate 1000- 999 + 998 -997 + ... + 4 - 3 + 2 - 1

Answer 4

500