This problem was used by students after working visually and conceptually to explain division with fractions. They use this problem as a transition to dividing fractions using the mulitplicative inverse. Students benefitted from constructing a diagram that showed the fence sections. Constructing the diagram on graph paper, using 20 squares for the length helped students divide equally and find the fraction they needed. Explaining the connections between the diagram and the equation are very important for constructing the argument.
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