Page 1 - HA
P. 1
SAI International School
Mathematics – Home Assignment
Chapter-5: Arithmetic Progression
Sub topics: Sum of ‘n’ terms
1. Find the sum of the following arithmetic progressions:
(i) 50, 46, 42, ... to 10 terms
(ii) 1, 3, 5, 7, ... to 12 terms
(iii) 3, 9/2, 6, 15/2, ... to 25 terms
(iv) 41, 36, 31, ... to 12 terms
2. How many terms are there in the A P. whose first and fifth terms are -14 and 2
respectively and the sum of the terms is 40?
3. Find the sum of n terms of an A.P. whose nth terms is given by a n = 5 - 6n.
th
4. Find the sum of first 20 terms the sequence whose n term is a n = An + B.
Answers-
1. (i) 320 (ii) 144 (iii) 525 (iv) 162
2. n = 10
3. n (2-3n)
4. 210 A + 20 B