Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

Session 4, Part B:
The Mixture Blues (45 minutes)

In This Part: Comparing Mixtures | Mixing Blues

 The scientists at the research lab for Whodunit Jeans are trying to decide on just the right shade of blue for a new line of jeans. Being scientists, not mathematicians, the researchers decide to choose a color by mixing pure blue liquid and clear water together until they get just the right shade. Note 3 The scientists have several beakers of liquid, some with blue liquid and some with clear water. They plan to mix these together in big bowls. Before they mix the liquids, they guess how blue the mixture will be. In Problems B1-B7, there are two sets (A and B) of blue-clear combinations to mix. Predict which set will be bluer, and explain your reasoning. Assume you do not know how to compare fractions with unlike denominators. (Converting to a common denominator and comparing would make these problems trivial.) Note 4 Problem B1

 Consider whether you are making absolute or relative comparisons in Problems B1-B7.   Close Tip Consider whether you are making absolute or relative comparisons in Problems B1-B7.

 Problem B2

 Problem B3

 Problem B4

 Problem B5

 Problem B6

 Problem B7

 Video Segment In this video segment, Frederick uses relative comparison to solve Problem B4. Watch this segment after you have completed Problems B1 through B7 and compare your reasoning with Frederick's. Why would an absolute comparison not be useful in solving Problems B1-B7? You can find this segment on the session video, approximately 18 minutes and 48 seconds after the Annenberg Media logo.

 Session 4: Index | Notes | Solutions | Video