Question

What is the sum of following series if the number of terms is 157.
4 + (-6) + 7 + (-8) + 9 + (-10) + ..... = ????
What is the answer? please solve^_^

Answer 1

Answer:

This question is wrong pls recheck the question because their common difference is not equal

a2-a1=-6-4=-10

And a3-a2=7-(-6)=13

Answer 2

given= n=157, a=4, d=-10

now, A. T. Q.

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

sn= 157/2(2.4+(157-1) (-10))

SN= 157/2(8-1560)

SN= 157/2(1552)

sn= 121832