What is the value of the expression 1 - 2 + 3 - 4 + 5 - 6 ........to 100 terms ?

-50

The value of the expression 1 - 2 + 3 - 4 + 5 - 6 ........to 100 terms 

According to the question, 1 - 2 = -1

Two terms are giving -1 result

So the total terms = 

The value of  the value of the expression 1 - 2 + 3 - 4 + 5 - 6 ........to 100 terms  = 50 × -1 = -50