Solution 1.2:4b

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Multiply top and bottom of the double fraction by the reciprocal of the denominator.
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<math>\frac{\frac{2}{7}}{\frac{3}{8}}=\frac{\frac{2}{7}\centerdot \frac{8}{3}}{\frac{3}{8}\centerdot \frac{8}{3}}=\frac{2}{7}\centerdot \frac{8}{3}</math>
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The numerator and denominator on the right-hand side do not have a common factor, so the answer is:
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<math>\frac{2}{7}\centerdot \frac{8}{3}=\frac{2\centerdot 8}{7\centerdot 3}=\frac{16}{21}</math>
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NOTE: It is also possible to learn a quick formula for double fractions which says that when the expression is rewritten with just one fraction sign, the denominators in the partial fractions change place:
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<math>\frac{\frac{2}{7}}{\frac{3}{8}}=\frac{2\centerdot 8}{3\centerdot 7}</math>

Revision as of 13:23, 11 September 2008

Multiply top and bottom of the double fraction by the reciprocal of the denominator.


\displaystyle \frac{\frac{2}{7}}{\frac{3}{8}}=\frac{\frac{2}{7}\centerdot \frac{8}{3}}{\frac{3}{8}\centerdot \frac{8}{3}}=\frac{2}{7}\centerdot \frac{8}{3}

The numerator and denominator on the right-hand side do not have a common factor, so the answer is:


\displaystyle \frac{2}{7}\centerdot \frac{8}{3}=\frac{2\centerdot 8}{7\centerdot 3}=\frac{16}{21}


NOTE: It is also possible to learn a quick formula for double fractions which says that when the expression is rewritten with just one fraction sign, the denominators in the partial fractions change place:


\displaystyle \frac{\frac{2}{7}}{\frac{3}{8}}=\frac{2\centerdot 8}{3\centerdot 7}

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