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प्रश्न
If the ratio of the sum of the first n terms of two A.Ps is (7n + 1) : (4n + 27), then find the ratio of their 9th terms.
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उत्तर
Suppose a1, a2 be the first terms and d1, d2 be the common differences of the two given A.Ps.
Then the sums of their n terms are
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