Set Up Proportions

Set up the following proportion:

Pens are 3 for $0.69 at the supply store. What proportion can be used to find c, the amount it will cost Mrs. Faber to buy 180 pens?

•  $\frac{3\ pens}{0.69\ dollars}=\frac{c}{180\ pens}$ 

•  $\frac{0.69\ dollars}{180\ pens}=\frac{c}{3\ pens}$ 

•  $\frac{3\ pens}{0.69\ dollars}=\frac{180\ pens}{c}$ 

Tags

CCSS.7.RP.A.2

CCSS.7.RP.A.3

Set up the following proportion:

It cost Jericho and his 3 friends $20 to get into the skating rink. What proportion can be used to find c, the amount it will cost Jericho’s parents if they have Jericho’s birthday party at the skating rink and pay for Jericho and all 24 of his classmates?

•  $\frac{4\ people}{20\ dollars}=\frac{25\ people}{c}$ 

•  $\frac{20\ dollars}{25\ people}=\frac{c}{4\ people}$ 

•  $\frac{c}{25\ people}=\frac{4\ dollars}{20\ dollars}$ 

Tags

CCSS.7.RP.A.2

CCSS.7.RP.A.3

Set up this proportion:

Vito uses 9 liters of water to water 24 flower pots. He is wondering how many liters of water (w), it would take to water 40 flower pots. He assumes he'll use the same amount of water on each pot.

• $\frac{9\ L}{40\ pots}=\frac{w}{24\ pots}$

• $\frac{9\ L}{24\ pots}=\frac{w}{40\ pots}$

• $\frac{24\ pots}{9\ L}=\frac{w}{40\ pots}$

Tags

CCSS.7.EE.B.4

CCSS.7.RP.A.2

CCSS.7.RP.A.3

Set up the following proportion:

Alice earned $20.40 in 3 hours. At the same rate, what would Alice make in 8 hours?

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  $\frac{20.40}{3\ hours}=\frac{x}{8\ hours}$

• $\frac{8\ hours}{20.40}=\frac{x}{3\ hours}$

• $\frac{3\ hours}{x}=\frac{20.40}{8\ hours}$

Tags

CCSS.7.RP.A.2

CCSS.7.RP.A.3

Is this a proportion?

*Are they equivalent fractions?*

• True

• False

Tags

CCSS.7.RP.A.2

CCSS.7.RP.A.3

We can tell if ratios are proportional by...

• top times top, bottom times bottom

• flipping the second and multiplying

• Cross Multiplying (Butterfly!!!)

Tags

CCSS.7.RP.A.2

CCSS.7.RP.A.3

Select ALL proportions that are set up correctly.

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Tags

CCSS.7.RP.A.2

CCSS.7.RP.A.3