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3 years ago

The cost of a pair of ice skates went from $200 to $140. What is the percent change in the cost of skates?

Mathematics

1 answer:

dmitriy555 [2]3 years ago

3 0

so the pair went down from 200 to 140, so the difference is 200 - 140 = 60.

so if we take 200 as the 100%, what is 60 off of it in percentage?

$\bf \begin{array}{ccll} amount&\%\\ \cline{1-2} 200&100\\ 60&x \end{array}\implies \cfrac{200}{60}=\cfrac{100}{x}\implies \cfrac{10}{3}=\cfrac{100}{x}\implies 10x=300 \\\\\\ x = \cfrac{300}{10}\implies x = 30$

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zlopas [31]

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egoroff_w [7]

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3 years ago

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kondor19780726 [428]

Indeed!

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Now set up an X(as I cannot draw very well in brainly it will look bad)

1 -3

\ /

/ \

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This might all look very confusing so let me explain it.

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The right side, -3*5=-15 which is the constant term.

What I did in the graph thing was to find 2 such pairs that line up in the graph in a way that the opposite corners multiplied and added together would = -1.

Such as the way I lined up the graph.

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As long as you find 2 such pairs you got the answer, just write it from left it right then top to bottom.

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Now we can always switch the ( ) as in this problem we can write the answer as (x-3)(2x+5) or switch it around as (2x+5)(x-3).

Therefore the answer A is the correct answer.

**If you have any questions about my explanation, simply ask me in the comment section and I will come answer. (I know my explanation here isn't the most clear so you probably will ask questions and please don't just put the answer in and be done with it, actually try to understand my explanation it will help with further questions like this.)

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