In the first problem from the string, students are asked:  Create an example of a composed unit for the ratio 75:15. Then, use a model to reveal a rate.  As always, value the voice of your students and do your best to model their thinking. While the context that students create for this composed unit ratio of 75:15, similar strategies may emerge such as using a fair sharing strategy to distribute 75 of a quantity into 15 groups (seeds to planter pots, goals to games played, etc.).   If students do not leverage any linear models, make an attempt to take their thinking and represent it using stacked bar models and/or a double number line then ask them if they can see their thinking in that model.
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