Question

1 ,2 ,3 .....are the AP then the sum of first 120 term is​

Answer 1

Answer:

7140

Step-by-step explanation:

step.1 The formula is n(n-1)÷2

so,120(120-1)÷2

:120(199)÷2

=7140

Answer 2

Answer:

below is your answer

hope it helps you thanks

Step-by-step explanation:

sum of first 120 terms are

first term is 1 and last term is 120 so sum is 120/2( 2+119))=121×120/2 =7260