Unit 7 Contents

Roberto solved the problem using the all-partials method of multiplication.

3. Explain where the partial product 80 came from.
4. Which of Irma's base-ten pieces model 80?
5. Explain where the partial product 1200 came from.
6. Which of Irma's base-ten pieces model 1200?

Shannon used rectangles to solve the problem.

7. How is Shannon's method similar to Roberto's?

John used expanded form to solve the airport lights problem.

8. How is John's method similar to Shannon's?
9. How do Irma's base-ten pieces model the parts of John's method?
10. Grace computed 3 306 like this:  
1. Estimate an answer to Grace's problem.
2. Is Grace's answer reasonable? Why or why not?
3. Why are there only two partial products in this problem?
4. Can you solve this problem using mental math? Explain.