Unit 4 Contents

3. Explain why there are four parts to Michael's and Roberto's rectangles. What does the area of each part represent?
1. Which part of Roberto's rectangle is the largest?
2. Which part of the rectangle is the smallest?
3. If you use Michael's or Roberto's method of multiplication with rectangles, will the largest and smallest rectangles always be in the same place? Explain your reasoning.
5. If you want to estimate an answer for 38 24, which part of the rectangle would you use? Explain your reasoning.
6. If you use the rectangle method to solve 326 73, how many smaller parts of the rectangle will there be? (You do not need to solve the multiplication problem.)

“I can show how the method works,” said Roberto. “The area of each part of the rectangle is a different piece of the multiplication problem.” He drew a diagram like this:

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Use Michael and Roberto's method to solve the problems on the Using Rectangles to Multiply pages in the Student Activity Book.