Question

4, +1, -2, ....., -53​

Answer 1

Answer:

-3+4-5+6-7+8-9+10-11+12-13+14-15+16

Answer 2

Answer:

I think in this question we need to find no. of terms that is n.....

a=4

d=1-4= -3

an=-53

an=a+(n-1)d

-53= 4 + (n-1)(-3)

-53-4=(n-1)(-3)

- 57 =(n-1)(-3)

-57/-3 =n-1

19 =n-1

n=20

Thus, no. of terms =20

Hope it helps u!!