Question

1+2+3+2+3+4+3+4+5....S39 find

Answer 1

Answer:

1+2+3+2+4+3+4+5+2+8+9 is the correct answer of 39

Answer 2

Answer:780

Step-by-step explanation:

Apply sn formula,sum=n/2(2a+(n-1)d)

S39=39/2(2(1)+(39-1)1

=39/2(40)

=780

Hope it helps.....