Proportion Models
Fold your graph paper into thirds
Label itShorts and pants
Chocolate chip and sugar cookies
Cats and pets
In Mrs. Durfee’s class, the ratio of students wearing shorts to students wearing pants is 1 to 3
Draw a model
In Mr. Prince’s class, the ratio of students wearing shorts to students wearing pants is 4 to 12
Draw a model
Compare the two models
Each model has 4 boxesEach box has the same amount of items
The ratios are proportional (equivalent)
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In one box of cookies, the ratio of chocolate chips cookies to sugar cookies is 3 to 8
Draw a model
A bigger box of cookies has the ratio of 12 to 32 chocolate chips cookies to sugar cookies
Draw a model
Each model has 11 boxesEach box has the same amount of items
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The ratio of cats to total pets at PetCo is 3 to 9. PetSmart’s ratio of cats to total pets is
6 to 18
Draw a model
The ratio of cats to total pets at PetCo is 3 to 9
PetSmart’s ratio of cats to total pets is 6 to 18
They are proportional
3 to 9
6 to 18
Same number of boxes
Equal amount of items in each box