Find the sum of the two middle most terms of the A.P.

Question

KnowledgeBoat · Accepted Answer

Here, a = We need to find the number of terms in the A.P. On multiplying both sides by 3, Since, A.P. has 18 terms, therefore 9th and 10th terms are two middle most terms. a₉ = a + (9 - 1)d = a + 8d (Eq 1) a₁₀ = a + (10 - 1)d = a + 9d (Eq 2) Adding Eq 1 and Eq 2, a₉ + a₁₀ = a + 8d + a + 9d = 2a + 17d. Hence, the sum of middle most terms Hence, the sum of the two middle most terms of the A.P. is equal to 3.

Mathematics

Find the sum of the two middle most terms of the A.P.

AP GP

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