Which term of the Arithmetic Progression (A.P.) 15, 30, 45, 60 ….. is 300 ? Hence find the sum of all terms of the Arithmetic Progression (A.P.).
AP GP
ICSE 2023
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Question

Which term of the Arithmetic Progression (A.P.) 15, 30, 45, 60 ..... is 300 ? Hence find the sum of all terms of the Arithmetic Progression (A.P.).

KnowledgeBoat · Accepted Answer

Given, A.P. : 15, 30, 45, 60 ..... First term (a) = 15 Common difference (d) = 30 - 15 = 15 Let nth term be 300. ⇒ an = 300 ⇒ a + (n - 1)d = 300 ⇒ 15 + 15(n - 1) = 300 ⇒ 15 + 15n - 15 = 300 ⇒ 15n = 300 ⇒ n = = 20. Sum of the terms of the given A.P. : ⇒ Sn = ⇒ S20 = = 10 × 315 = 3150. Hence, sum of all terms of the given A.P. = 3150.

Mathematics

Which term of the Arithmetic Progression (A.P.) 15, 30, 45, 60 ….. is 300 ? Hence find the sum of all terms of the Arithmetic Progression (A.P.).

AP GP

ICSE 2023

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