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2 years ago

Find the sum of ∑4/k=1 (-4k)

Mathematics

1 answer:

Annette [7]2 years ago

4 0

Answer:

Hello,

Answer C: -40

Step-by-step explanation:

$\displaystyle \sum_{k=1}^4\ (-4k)\\\\=-4*\sum_{k=1}^4\ k\\\\=-4*4*\dfrac{1+4}{2} \\\\=-4*5*2\\\\=-40\\$

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Elenna [48]

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3 years ago

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Step-by-step explanation:

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Now, utilities percent change for 2010 to 2020 : $\dfrac{change \ in \ job\ numbers}{Initial\ jobs}\times 100$

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3 years ago

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Answer:

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Step-by-step explanation:

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Answer:

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