progression

Question

If the ratio of the sums of first p terms and q terms of an AP is p^2 : q^2 , then the ratio of its pth and qth terms is :
a. (2p-1) : (2q-1)
b. (2p+1) : (2q+1)
c. p : q
d. (p+1) : (q+1)

Answer 1

So Option A 2p-1 : 2q-1 

let me know if anything wrong

Answer 2

We can also solve it like this :

 We know nth term of AP t_n = S_n - S_n-1   ( where S_n means sum of n terms)

So if sum of p terms = p² (say)

        sum of (p-1) terms = (p-1)²

Hence , pth term can be written as :  p² - (p-1)²  =   2p - 1

Similarly qth term can be written as : q² - (q-1)² = 2q -1

Hence the ratio of pth and qth term : (2p-1)  /   (2q-1)

Hence  the correct option is A)