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What is ∑n=17(10n+90) equal to?

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What is ∑n=17(10n+90) equal to? Enter your answer in the box.-example-1
User Pzelasko
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1 Answer

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Answer:

910

Explanation:


\sum_(n=1)^(7)(10n+90)\\\\=\sum_(n=1)^(7)(10n)+\sum_(n=1)^(7)(90)\\\\=10\sum_(n=1)^(7)(n)+90(7)\\\\=10((7(7+1))/(2))+630\\\\=10(28)+630\\\\=280+630\\\\=910

User Anrimian
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