When using this activity I like to de-emphasize the use of cross-multiplication (In general, I have found that the use of cross-multiplication does not lead to a better/deeper understanding of…
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Detailed information about How Many Miles To…
Mathematics > General Mathematics > Arithmetic
Creative Commons Attribution 3.0
Created by: Darlene Diaz, Santiago Canyon College
Type of activity: hands on activity, individual, small group problem solving (paper and pencil)
Course level: Basic (Essential) Math
Materials: map, ruler
Time required: 30 minutes
Description: By using a map and a ledger on the map, the student will use a proportion to calculate how many actual miles from one destination to another. Have each student measure how many inches from the first destination to the second destination. The student will set up a proportion and calculate how many actual miles. (See attached worksheet)
Implementation notes (follow up/discussion questions, pedagogical recommendations, etc.): Be sure to show an example so that they have a clear idea what is expected. You can also have a map in the classroom and have each student measure with a yard stick or use a transparency. Feel free to use any map- the world, nation, state, etc. You can also use a group setting, e.g., small groups of 3, one group with volunteers.
Related activities: Have students create a scale model of the classroom or one of the structures on campus. Before they start, be sure to have them think carefully about the scale factor that they'll use. How should they choose their scale factor? You might ask them, for example, if it would make sense to let let 1 inch represent 1 foot if they intend to draw their model on an 8.5" by 11" piece of paper.