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Given that 21 over π is equal to seven over nine which is equal to π over 36, find the values of π and π.
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First, we can just copy down the proportion.
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We notice that our only full fraction is the one in the middle β seven over nine.
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We can use this seven over nine to help us find π and π.
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I know that to go from seven to 21, you multiply seven by three.
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I also know that when weβre working with fractions, if I multiply the numerator by a value, I must multiply the denominator by the same value.
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And that means that π must be equal to nine times three.
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Nine times three is 27.
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π is equal to 27.
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We can use this same process to find π.
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I notice that nine times four equals 36.
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If I multiply the denominator by a value, I must multiply the numerator by the same value.
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Seven times four equals 28.
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π must be equal to 28.
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The completed proportion looks like this: 21 over 27 is equal to seven over nine which is equal to 28 over 36.