Question

first term =-5 last term =45if the sum of all number is 120 , then how many term are there ​

Answer 1

Step-by-step explanation:

Sn=n/2(a+l)

Sn denote sum of terms

n denote no. of terms

a denote first term

l denote Last term

120=n/2(-5+45)

120×2=n(40)

240/40=n

6=n