Solution 1.2:1d

From Förberedande kurs i matematik 1

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
When we have three fractions involved in an addition, we need to multiply the top and bottom of each fraction by the product of the other fraction's denominators so that all fractions have a common denominator,
When we have three fractions involved in an addition, we need to multiply the top and bottom of each fraction by the product of the other fraction's denominators so that all fractions have a common denominator,
-
 
+
<center><math>\frac{1\centerdot 4\centerdot 5}{3\centerdot 4\centerdot 5}+\frac{1\centerdot 3\centerdot 5}{4\centerdot 3\centerdot 5}+\frac{1\centerdot 3\centerdot 4}{5\centerdot 3\centerdot 4}=\frac{20}{60}+\frac{15}{60}+\frac{12}{60}</math></center>
-
<math>\frac{1\centerdot 4\centerdot 5}{3\centerdot 4\centerdot 5}+\frac{1\centerdot 3\centerdot 5}{4\centerdot 3\centerdot 5}+\frac{1\centerdot 3\centerdot 4}{5\centerdot 3\centerdot 4}=\frac{20}{60}+\frac{15}{60}+\frac{12}{60}</math>
+
When all three fractions have a common denominator, they can easily be added up
When all three fractions have a common denominator, they can easily be added up
-
 
+
<center><math>\frac{20}{60}+\frac{15}{60}+\frac{12}{60}=\frac{20+15+12}{60}=\frac{47}{60}</math></center>
-
<math>\frac{20}{60}+\frac{15}{60}+\frac{12}{60}=\frac{20+15+12}{60}=\frac{47}{60}</math>
+

Revision as of 12:08, 11 September 2008

When we have three fractions involved in an addition, we need to multiply the top and bottom of each fraction by the product of the other fraction's denominators so that all fractions have a common denominator,

\displaystyle \frac{1\centerdot 4\centerdot 5}{3\centerdot 4\centerdot 5}+\frac{1\centerdot 3\centerdot 5}{4\centerdot 3\centerdot 5}+\frac{1\centerdot 3\centerdot 4}{5\centerdot 3\centerdot 4}=\frac{20}{60}+\frac{15}{60}+\frac{12}{60}

When all three fractions have a common denominator, they can easily be added up

\displaystyle \frac{20}{60}+\frac{15}{60}+\frac{12}{60}=\frac{20+15+12}{60}=\frac{47}{60}