MEDIUM
11th Assam Board
IMPORTANT
Earn 100

Let the sum of n,2n,3n terms of an A.P. be S1,S2 and S3 respectively, show that S3=3(S2-S1)

Important Questions on Sequences and Series

MEDIUM
11th Assam Board
IMPORTANT
Find the sum of all numbers between 200 and 400 which are divisible by 7.
HARD
11th Assam Board
IMPORTANT
Find the sum of integers from 1 to 100 that are divisible by 2 or 5.
MEDIUM
11th Assam Board
IMPORTANT
Find the sum of all two-digit numbers which when divided by 4, yields 1 as remainder.
MEDIUM
11th Assam Board
IMPORTANT
If f is a function satisfying fx+y=fx.fy for all x, yN, such that f1=3 and Σ1nfx=120, find the value of n.
MEDIUM
11th Assam Board
IMPORTANT
The sum of some terms of G.P. is 315 whose first term and the common ratio are 5 and 2, respectively. Find the last term and the number of terms.
EASY
11th Assam Board
IMPORTANT
The first term of a G.P. is 1. The sum of the third term and fifth term is 90. Find the common ratio of  G.P.
MEDIUM
11th Assam Board
IMPORTANT
The sum of three numbers in G.P. is 56. If we subtract 1,7,21 from these numbers n in that order, we obtain an arithmetic progression. Find the numbers.
HARD
11th Assam Board
IMPORTANT
A G.P. consists of an even number of terms. If the sum of all the terms is 5 times the sum of terms occupying odd places, then find its common ratio.