WEBVTT

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Here is the problem: 6 plus 12 times (4 minus 9) / 7.

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Exact arithmetic with fractions (results kept in lowest terms).

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Subtract the whole numbers.

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Multiply numerators and multiply denominators.

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Dividing by a fraction means multiplying by its reciprocal.

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Multiply numerators and multiply denominators.

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Rewrite both fractions with the least common denominator. The LCD of 1 and 7 is 7.

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Add the numerators and keep the denominator.

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Final answer in lowest terms.

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So the answer is negative 18 over 7.

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Fractions are combined over a common denominator for addition and subtraction, multiplied straight across, and divided by multiplying by the reciprocal. The result is reduced by the greatest common factor.

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Decimal check: negative 18 over 7 approximately negative 2.571428571.

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As a mixed number: negative 2 4 over 7.