SOLUTION: Solve the proportion. k/28=8/63

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Question 110626: Solve the proportion.
k/28=8/63

Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
Given the proportion:
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k%2F28=8%2F63
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You can start the solution to proportion problems by using a process called "cross multiplying."
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In this process you multiply the numerator of one side times the denominator of the other
side, then write the equal sign, and follow that by multiplying the numerator of the other
side by the denominator of the first side. A little difficult to describe, but actually
pretty easy to do once you get the hang of it.
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In this problem we can begin by multiplying the k (a numerator) times the 63 (the denominator
from the other side), then write the equal sign, and on the other side of the equal sign
multiply the 8 (a numerator) times the 28 (denominator from the opposite side).
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When you do that you have:
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63%2Ak+=+8%2A28
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Now you can solve for k by dividing both sides by 63 (the multiplier of k) to get:
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k+=+%288%2A28%29%2F63
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Notice that 63 factors into 9 times 7. Therefore, you can replace the 63 with 9*7 and the
problem then becomes:
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k+=+%288%2A28%29%2F%289%2A7%29
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And the 28 in the numerator factors into 7 times 4. So replace the 28 with 7*4 and the
problem is then:
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k+=+%288%2A7%2A4%29%2F%289%2A7%29
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You can then cancel the 7 in the numerator with the 7 in the denominator and you have:
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k+=+%288%2Across%287%29%2A4%29%2F%289%2Across%287%29%29+=+%288%2A4%29%2F9+
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Nothing else will cancel nicely, so multiply out the numerator and divide that product
by the denominator to get:
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k+=+%288%2A4%29%2F9+=+32%2F9+=+3.555556
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Hope this helps you. The cross process of cross multiplying is a convenient way to remember
what to do to convert proportions to an ordinary algebraic equation. You might want to
remember it.
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