1. COFFEE PROBLEM
Consider the following two coffee mixes.
In mix A the ratio of milk to coffee is 2 : 3. In mix B the ratio of milk to coffee is 3 : 4.
Which recipe will make coffee that is the most “milky”? Solve the problem in two different ways.
In one of these ways, solve the problem without using fractions, percentages, or decimals. Use a
diagram to show why your strategy works. Record your solution and diagram on chart paper.

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Ben said he used percentages to figure out which mix will be the most “milky”. See his work below.
Does his strategy make sense?
Mix A:
2 : 3
Amanda disagrees. She claims that they are equally “milky” because they each have one more unit
of coffee than milk. Does her thinking make sense?
What might you ask or what comment would you make in response to these student strategies?