From: Cathy Fossum
To: Teacher2Teacher Public Discussion
Subject: dividing fractions
I agree with Rick that students need a number of concrete experiences in understanding the concept of dividing by fractions first. Then they will be better prepared to understand the algorithm. In the example he gave, 3 divided by 3/4, I find it easiesr to understand the algorithm when using a subtracting equal groups model of division (as opposed to a sharing model.) To find out how many 3/4's are in 3, first you need to know how many fourths there are. 3 wholes X 4 fourths in each equals 12 fourths in all. Then you need to take out all the possible groups of 3 fourths which is dividing by 3. Therefore, the answer is 3 X 4/3. Actually, I just recently came to this idea at a boring teachers' meeting. My fifth graders already understand the concept of dividing by fractions. After vacation I need to give them experiences to help them understand this algorithm. It's intriguing to try to design experiences that will promote this. Any suggestions?
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