Find the sum of all natural numbers between 250 and 1000 which are divisible by 9.
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Question

Find the sum of all natural numbers between 250 and 1000 which are divisible by 9.

KnowledgeBoat · Accepted Answer

. The numbers which are divisible by 9 between 250 and 1000 are, = 28 × 9, 29 × 9, 30 × 9, ............, 111 × 9. = 252, 261, 270, .........., 999. The above sequence is an A.P. with common difference = 9 and first term = 252 and last term = 999. Let n be no. of terms, ∴ a_n = a + (n - 1)d ⇒ 999 = 252 + (n - 1)9 ⇒ 999 = 252 + 9n - 9 ⇒ 999 = 9n + 243 ⇒ 999 - 243 = 9n ⇒ 9n = 756 ⇒ n = 84. Hence, sum = 52542.

Mathematics

Find the sum of all natural numbers between 250 and 1000 which are divisible by 9.

AP

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Mathematics

Find the sum of all natural numbers between 250 and 1000 which are divisible by 9.

AP

Related Questions

The sum of first 7 terms of an A.P. is 49 and that of first 17 terms of it is 289. Find the sum of first n terms.

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