Find the value of each expression mentally. 

1. For each diagram, write a multiplication expression that the diagram can represent. Then find the value of the expression. Use equations to explain or show your reasoning.

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      Diagram, rectangle partitioned vertically and horizontally into 4 rectangles. Top left rectangle, vertical side, 10, horizontal side, 10. Top right rectangle, horizontal side, 8. Bottom 2 rectangles, vertical side, 6.
2. How are these diagrams alike? How are they different? Discuss with your partner.

3. Use a diagram to find each product.

These diagrams could be used to find the value of .

Diagram, rectangle partitioned vertically and horizontally into 4 rectangles. Top left rectangle, vertical side, 40, horizontal side, fifty. Top right rectangle, horizontal side, 7. Bottom 2 rectangles, vertical side, 9.

Diagram, rectangle partitioned vertically and horizontally into 4 rectangles. Top left rectangle, vertical side, 37, horizontal side, fifty. Top right rectangle, horizontal side, 7. Bottom 2 rectangles, vertical side 12.

1. Which diagram is more helpful when finding the value of ?  Why?

2. Use a diagram to find each product.