The ratio of the sums of n terms of two aps is 7n+1 : (4n + 27 find the ratio of their 11th terms)

Given: Ratio of sum of nth terms of 2 AP’s
To Find: Ratio of their 11th terms

Let us consider 2 AP series AP1 and AP2. Putting n = 1, 2, 3… we get AP1 as 8, 15 22… and AP2 as 31, 35, 39…. So, a1 = 8, d1 = 7 and a2 = 31, d2 = 4 For AP1 S6 = 8 + (11 – 1)7 = 87 For AP2 S6 = 31 + (11 – 1)4 = 81

Required ratio =

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