Solution 1.2:3a

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Current revision (07:55, 19 September 2008) (edit) (undo)
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The denominator in the expression has
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The denominator in the expression has 10 as a common factor,
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<math>10</math>
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as a common factor,
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<math>\frac{3}{2\centerdot 10}+\frac{7}{5\centerdot 10}-\frac{1}{10}</math>
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{{Displayed math||<math>\frac{3}{2\cdot 10}+\frac{7}{5\cdot 10}-\frac{1}{10}\,</math>,}}
and it is therefore sufficient to multiply the top and bottom of each fraction by the other factors in the denominators in order to obtain a common denominator,
and it is therefore sufficient to multiply the top and bottom of each fraction by the other factors in the denominators in order to obtain a common denominator,
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{{Displayed math||<math>\frac{3\cdot 5}{20\cdot 5}+\frac{7\cdot 2}{50\cdot 2}-\frac{1\cdot 5\cdot 2}{10\cdot 5\cdot 2}=\frac{15}{100}+\frac{14}{100}-\frac{10}{100}\,</math>.}}
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<math>\frac{3\centerdot 5}{20\centerdot 5}+\frac{7\centerdot 2}{50\centerdot 2}-\frac{1\centerdot 5\centerdot 2}{10\centerdot 5\centerdot 2}=\frac{15}{100}+\frac{14}{100}-\frac{10}{100}</math>
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The lowest common denominator (LCD) is therefore 100, and the expression is equal to
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The lowest common denominator (LCD) is therefore
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<math>100</math>
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, and the expression is equal to
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<math>\frac{15}{100}+\frac{14}{100}-\frac{10}{100}=\frac{15+14-10}{100}=\frac{19}{100}</math>
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{{Displayed math||<math>\frac{15}{100}+\frac{14}{100}-\frac{10}{100}=\frac{15+14-10}{100}=\frac{19}{100}\,</math>.}}

Current revision

The denominator in the expression has 10 as a common factor,

\displaystyle \frac{3}{2\cdot 10}+\frac{7}{5\cdot 10}-\frac{1}{10}\,,

and it is therefore sufficient to multiply the top and bottom of each fraction by the other factors in the denominators in order to obtain a common denominator,

\displaystyle \frac{3\cdot 5}{20\cdot 5}+\frac{7\cdot 2}{50\cdot 2}-\frac{1\cdot 5\cdot 2}{10\cdot 5\cdot 2}=\frac{15}{100}+\frac{14}{100}-\frac{10}{100}\,.

The lowest common denominator (LCD) is therefore 100, and the expression is equal to

\displaystyle \frac{15}{100}+\frac{14}{100}-\frac{10}{100}=\frac{15+14-10}{100}=\frac{19}{100}\,.
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