Solving Problems with Proportions

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply the two ratios and set the products equal to each other.

Front

What is the formula for finding a missing value in a proportion?

Back

If a/b = c/d, then ad = bc. You can find the missing value by rearranging this equation.

Front

If 1 Euro is worth 1.07 US Dollars, how much is 20 Euros worth?

Back

20 Euros is worth 21.40 US Dollars.

Front

How do weight differences on Earth and the Moon illustrate proportions?

Back

Weight on the Moon is a proportion of weight on Earth, calculated using the ratio of their gravitational forces.

Front

If an astronaut weighs 85 kg on Earth, how much would they weigh on the Moon?

Back

They would weigh 14.2 kg on the Moon.

Front

If a person weighs 95 kg on Earth, how much would they weigh on the Moon?

Back

They would weigh approximately 15.9 kg on the Moon.

Front

What is the relationship between recipe ingredients and proportions?

Back

The amounts of ingredients in a recipe can be scaled up or down while maintaining the same proportions.

Front

If a recipe for 4.5 cups of granola requires 1.5 cups of raisins, how many cups are needed for 18 cups?

Back

You would need 6 cups of raisins.

Front

How do you convert rates to find amounts over different time periods?

Back

To convert rates, divide the total amount by the time period to find the amount per smaller time unit.