If the sum of first 14 terms of an A.P. is 1050 and its first term is

1.	If the sum of first 14 terms of an A.P. is 1050 and its first term is 10, find the 20th term.
Answer» Let common difference be ݀ ⇒ 14/2 [2(10) + (݊ − 1)݀] = 1050 ⇒ d = 10 a₂₀ = a + 19d = 10 + 19 (10) = 200

If the sum of first 14 terms of an A.P. is 1050 and its first term is 10, find the 20th term.

Answer»

Let common difference be ݀

⇒ 14/2 [2(10) + (݊ − 1)݀] = 1050

⇒ d = 10

a₂₀ = a + 19d

= 10 + 19 (10) = 200

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If the sum of first 14 terms of an A.P. is 1050 and its first term is 10, find the 20th term.

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