From Förberedande kurs i matematik 1

Revision as of 10:00, 26 March 2008 (edit) Lina (Talk | contribs) (Ny sida: {{NAVCONTENT_START}} <center> Bild:1_2_3a.gif </center> {{NAVCONTENT_STOP}}) ← Previous diff		Current revision (07:55, 19 September 2008) (edit) (undo) Tek (Talk | contribs) m
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-	{{NAVCONTENT_START}}	+	The denominator in the expression has 10 as a common factor,
-	<center> [[Bild:1_2_3a.gif]] </center>	+
-	{{NAVCONTENT_STOP}}	+	{{Displayed math||<math>\frac{3}{2\cdot 10}+\frac{7}{5\cdot 10}-\frac{1}{10}\,</math>,}}
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		+	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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		+	The lowest common denominator (LCD) is therefore 100, and the expression is equal to
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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>.}}

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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}\,.