Q.9.(a). Find the sum first n natural numbers.
(b). The first letter of an AP is 5. the last is 45 and the sum is 400. Find the number of terms and the common difference.
Kindly refer the same link for your query.
a https://www.meritnation.com/ask-answer/question/find-the-sum-of-first-n-natural-numbers/arithmetic-progressions/8883777
b Kindly refer the similar link for your query.
https://www.meritnation.com/ask-answer/question/the-first-term-of-an-ap-is-5-and-the-last-term-45-and-the/arithmetic-progressions/11022544
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a https://www.meritnation.com/ask-answer/question/find-the-sum-of-first-n-natural-numbers/arithmetic-progressions/8883777
b Kindly refer the similar link for your query.
https://www.meritnation.com/ask-answer/question/the-first-term-of-an-ap-is-5-and-the-last-term-45-and-the/arithmetic-progressions/11022544
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