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$\\dfrac{\\var{a1}}{\\var{b1}} + \\dfrac{\\var{c1}}{\\var{d1}}$

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In lowest terms, the numerator is [[0]], the denominator is [[1]]

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$\\dfrac{\\var{a1}}{\\var{b1}} - \\dfrac{\\var{c1}}{\\var{d1}}$

In lowest terms, the numerator is [[0]], the denominator is [[1]]

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$\\dfrac{\\var{a1}}{\\var{b1}} \\times \\dfrac{\\var{c1}}{\\var{d1}}$

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In lowest terms, the numerator is [[0]], the denominator is [[1]]

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$\\dfrac{\\var{a1}}{\\var{b1}} \\div \\dfrac{\\var{c1}}{\\var{d1}}$

In lowest terms, the numerator is [[0]], the denominator is [[1]]

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Evaluate the following as fractions in lowest terms. Write the numerator and denominator of the lowest term fraction in the boxes provided.

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Questions testing understanding of numerators and denominators of numerical fractions, and reduction to lowest terms.

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For addition and subtraction, write fractions so that they have a common denominator and then perform addition or subtraction on the numerators. One method of doing this is 'cross-multiplication'. The rules are :

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\\[\\simplify{a/b+ c/d=(a*d+b*c)/(b*d)}.\\]
\\[\\simplify{a/b- c/d=(a*d-b*c)/(b*d)}.\\]

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For multiplication and division the rules are simpler:

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\\[\\simplify{(a/b)} \\times \\simplify{(c/d)}=\\simplify{(a*c)/(b*d)}.\\]
\\[\\simplify{(a/b)} / \\simplify{(c/d)}=\\simplify{(a*d)/(b*c)}.\\]

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Having applied these rules, it will be necessary to reduce the resulting fractions to lowest terms. We get:

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a) $\\dfrac{\\var{a1}}{\\var{b1}} + \\dfrac{\\var{c1}}{\\var{d1}}=\\dfrac{\\var{a1} \\times \\var{d1} + \\var{b1} \\times \\var{c1}}{\\var{b1} \\times \\var{d1}}=\\dfrac{\\var{a1*d1 + b1*c1}}{\\var{b1*d1}}$. In lowest terms this is $\\dfrac{\\var{(a1*d1 + b1*c1)/f1}}{\\var{b1*d1/f1}}$.

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b) $\\dfrac{\\var{a1}}{\\var{b1}} - \\dfrac{\\var{c1}}{\\var{d1}}=\\dfrac{\\var{a1} \\times \\var{d1} - \\var{b1} \\times \\var{c1}}{\\var{b1} \\times \\var{d1}}=\\dfrac{\\var{a1*d1 - b1*c1}}{\\var{b1*d1}}$. In lowest terms this is $\\dfrac{\\var{(a1*d1 - b1*c1)/g1}}{\\var{b1*d1/g1}}$.

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c) $\\dfrac{\\var{a1}}{\\var{b1}} \\times \\dfrac{\\var{c1}}{\\var{d1}}=\\dfrac{\\var{a1} \\times \\var{c1}}{\\var{b1} \\times \\var{d1}}=\\dfrac{\\var{a1*c1}}{\\var{b1*d1}}$. In lowest terms this is $\\dfrac{\\var{a1*c1/h1}}{\\var{b1*d1/h1}}$

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d) $\\dfrac{\\var{a1}}{\\var{b1}} \\div \\dfrac{\\var{c1}}{\\var{d1}}=\\dfrac{\\var{a1}}{\\var{b1}} \\times \\dfrac{\\var{d1}}{\\var{c1}}=\\dfrac{\\var{a1} \\times \\var{d1}}{\\var{b1} \\times \\var{c1}}=\\dfrac{\\var{a1*d1}}{\\var{b1*c1}}$. In lowest terms this is $\\dfrac{\\var{a1*d1/j1}}{\\var{b1*c1/j1}}$

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