To solve a problem like this, you can use a method called cross-multiplying. This is when you multiply the denominator of the first fraction by the numerator of the other and then multiply the two remaining numbers.
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Multiply 3 by 6 and multiply 4 by x.
4x = 18 Divide by 4.
x =
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Simplify!
x =
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You can check this by comparing the fractions with
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in the place of x.
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Divide
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by 6 (
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times
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).
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Simplify!

The fractions are equal, so
x =
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.