Ratios, Unit Rates, Proportions

Front

What is a ratio?

Back

A ratio is a comparison of two quantities by division, showing how many times one value contains or is contained within the other.

Front

How do you find a unit rate?

Back

To find a unit rate, divide the quantity by the number of units. For example, if you travel 150 miles on 5 gallons, the unit rate is 150 miles ÷ 5 gallons = 30 miles per gallon.

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal. For example, if a:b = c:d, then a/b = c/d.

Front

How can you determine if two ratios are equivalent?

Back

Two ratios are equivalent if their cross products are equal. For example, for ratios a:b and c:d, they are equivalent if a*d = b*c.

Front

What is the unit rate of 60 miles in 2 hours?

Back

The unit rate is 30 miles per hour, calculated by dividing 60 miles by 2 hours.

Front

If a recipe calls for 2 cups of flour for every 3 cups of sugar, what is the ratio of flour to sugar?

Back

The ratio of flour to sugar is 2:3.

Front

What is the better value: 5 pounds of apples for $10 or 3 pounds for $6?

Back

5 pounds for $10 is $2 per pound, while 3 pounds for $6 is $2 per pound. They are equivalent in value.

Front

If you earn $12 every 4 hours, how much do you earn per hour?

Back

You earn $3 per hour, calculated by dividing $12 by 4 hours.

Front

What is the ratio of 8 to 12 in simplest form?

Back

The simplest form of the ratio 8:12 is 2:3.

Front

If the ratio of boys to girls in a class is 4:5 and there are 20 boys, how many girls are there?

Back

There are 25 girls, calculated using the proportion 4/5 = 20/x.