Unit 10 Contents

Use the Multiplication and Division Facts page and the pages related to fractions in the Student Guide Reference section as needed.

1. Do you agree with Jerome and Jackie's answer? Explain why or why not.
2. How is Jerome's method of finding a common denominator like Jackie's method of covering both fractions with a single color?
3. Use circle pieces to explain why Jerome multiplies the numerator and denominator of by 3.
4. Use circle pieces to explain why Jerome multiplies the numerator and denominator of by 2.
5. Would Jerome's method still work if he used 24 as a common denominator instead of 12? Show how you know.

Jackie wants to find out if these methods work for subtracting fractions. “Why don't we try?” says Mr. Moreno. He writes this subtraction problem on the board.

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1. Find the lowest common denominator for the two fractions. Explain how you know it is the lowest one.
2. Calculate the answer to Mr. Moreno's subtraction problem using Jerome's method.
1. Calculate the answer to Mr. Moreno's subtraction problem using Jackie's method.
2. What single-color pieces did you use?
3. Did you get the same answer you got using Jerome's method? Why or why not?
6. Find the fraction sums and differences below. Choose an efficient method for each problem. Estimate to see if your answers are reasonable.
1. +
2. −
3. +
4. −
5. + +
6. + −
7. Make a drawing that shows how to use circle pieces of one color to check your answers for Questions 6A and 6B.
8. Show how you estimated to check if your answers to Questions 6E and 6F are reasonable.