The ratio of the sum of n terms of two A.P.s is (7n+1):(4n+27).Find the ratio of their mth term.

The ratio of the sum of n terms of two A.P.s is (7n+1):(4n+27).Find th

1.	The ratio of the sum of n terms of two A.P.s is (7n+1):(4n+27).Find the ratio of their mth term.
Answer» We know n th term of AP can be written as an= sn - s(n-1)i.e. nth term of AP = sum of first n terms - sum of first (n-1) termsNow,s1n/s2n= (7n+1)/(4n+27)Let ‘k’ be common multiple thens1n = (7n+1)k and s2n= (4n+27)kNow ‘m’ th term of AP1 will be a1m= s1m – s1(m-1)a1m= (7m+1)k – (7(m-1)+1)k= (7m+1-7m+7-1)k=7kNow ‘m’ th term of AP2 will bea2m = (4m+27)k – (4(m-1)+27)k= (4m+27-4m+4-27)k = 4ktherefore , a1m/a2m= 7k/4k=7/4Ans. 7/4\xa0 Try once more ...here it can\'t be solved !! Try again urself