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1 vote
I need help on adding mixed fractions with unlike denominators

I need help on adding mixed fractions with unlike denominators-example-1
User Lab
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2 Answers

4 votes
we'll first convert the mixed fractions to "improper", and proceed from there,


\bf \stackrel{mixed}{7(1)/(9)}\implies \cfrac{7\cdot 9+1}{9}\implies \stackrel{improper}{\cfrac{64}{9}} \\\\\\ \stackrel{mixed}{8(2)/(5)}\implies \cfrac{8\cdot 5+2}{5}\implies \stackrel{improper}{\cfrac{42}{5}}\\\\ -------------------------------\\\\ 7(1)/(9)+8(2)/(5)\implies \cfrac{64}{9}+\cfrac{42}{5}\impliedby \textit{our LCD will be }45\implies \cfrac{(5)64~+~(9)42}{45} \\\\\\ \cfrac{320+378}{45}\implies \cfrac{698}{45}\implies 15(23)/(45)
User Covadonga
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6.5k points
2 votes
It’s about 15.5111, It’s ok if you don’t get it, just simplify it to get a improper fraction and change the denominator to a similar number as the other.
User Remo
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6.1k points