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Constructing proportions

4 videos
3 skills
Your knowledge of ratios has extended into understanding proportions. (If not, back up and be sure you get it!) Now that we know what a proportional relationship is, let's construct some real problems to solve. In this group of tutorials we'll practice writing and solving proportions, with both known and unknown variables. Common Core Standards: 7.RP.A.2, 7.RP.A.3

Writing proportions

VIDEO 5:51 minutes
As opposed to actually solving ratio word problems, in this video we'll practice just setting up the equations to solve them. Watch as we set up proportions to get at the answers.

Writing proportions

PRACTICE PROBLEMS

Solve a proportion with unknown variable

VIDEO 7:20 minutes
Here's a great video where we explain the reasoning behind solving proportions. We'll put some algebra to work to get our answers, too.

Solve a proportion with unknown variable word problem

VIDEO 5:48 minutes
Need to increase a recipe by 2 or 3 times in order to feed more guests? Ok, to do that you would need to construct proportions and solve for variables. We'll demonstrate here.

Proportions 1

PRACTICE PROBLEMS

Constructing equations from proportions to solve problems

VIDEO 4:58 minutes
We're putting some nifty thinking to work as we use proportions to create equations which then tell us how much tip to leave for dinner.