Question

(b) Find the sum of first twenty terms of the following arithmetic progressions A.P
(i) -4,-1, 2,...
(ii) 2, 3, 5,...
(iii) -2, -5, -8, -11,...

Answer 1

Answer:

-4*20+3*190=490

2*20+190=230

-2*20-3*190=-610