ProudGrandma Posted September 13, 2012 Share Posted September 13, 2012 my daughter is really struggling with all of the steps to solve unlike denominators for 3 fractions. how can I explain this to her in an easier to understand way? Quote Link to comment Share on other sites More sharing options...

Trillian Posted September 13, 2012 Share Posted September 13, 2012 I tried to explain the other ways to my son and he said "I understand perfectly well how to do it this way." And that was that. (We don't watch the DVDs, so he hadn't seen the explanations at all). I don't think learning all the ways are necessary, because eventually Epsilon will teach finding the LCD and adding and subtracting using it. Of course, I use MUS because DS likes it (not the videos) but I don't so I feel free to change things at will. Quote Link to comment Share on other sites More sharing options...

5LittleMonkeys Posted September 14, 2012 Share Posted September 14, 2012 Method #2 is just unnecessarily confusing in my opinion. Skip it. First try to find a common denominator for all three fractions. For example in this problem: 1/2 + 1/4 + 1/6= You would use 12 as the common denominator of all three so you would end up with: 6/12 + 3/12 + 2/12 = 11/12 If you can't find a common denominator for all three, as in this problem: 1/2 + 1/3 + 1/7 = Then find a common denominator of the first two fractions and then a common denominator of that answer and the third fraction. So you would use 6 as the common denominator of: 1/2 + 1/3 = Which would give you: 3/6 + 2/6 = 5/6 Then you would use 42 as the common denominator for: 5/6 + 1/7 = Which would give you: 35/42 + 6/42 = 41/42 Hope that helps! Quote Link to comment Share on other sites More sharing options...

ProudGrandma Posted September 15, 2012 Author Share Posted September 15, 2012 Method #2 is just unnecessarily confusing in my opinion. Skip it. First try to find a common denominator for all three fractions. For example in this problem: 1/2 + 1/4 + 1/6= You would use 12 as the common denominator of all three so you would end up with: 6/12 + 3/12 + 2/12 = 11/12 If you can't find a common denominator for all three, as in this problem: 1/2 + 1/3 + 1/7 = Then find a common denominator of the first two fractions and then a common denominator of that answer and the third fraction. So you would use 6 as the common denominator of: 1/2 + 1/3 = Which would give you: 3/6 + 2/6 = 5/6 Then you would use 42 as the common denominator for: 5/6 + 1/7 = Which would give you: 35/42 + 6/42 = 41/42 Hope that helps! that DOES help...thanks. I think she might actually get this. Quote Link to comment Share on other sites More sharing options...

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