Proportions

Front

What is a proportion?

Back

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

Front

How do you find the unit rate?

Back

To find the unit rate, divide the quantity by the number of units. For example, if a car travels 300 miles in 5 hours, the unit rate is 300 miles ÷ 5 hours = 60 miles per hour.

Front

What is the formula for calculating a rate?

Back

Rate = Quantity / Time.

Front

If 4 apples cost $2, how much do 10 apples cost?

Back

If 4 apples cost $2, then 10 apples cost $5 (using the unit rate: $2/4 apples = $0.50 per apple, then $0.50 x 10 apples = $5).

Front

What is the relationship between fractions and decimals?

Back

Fractions can be converted to decimals by dividing the numerator by the denominator.

Front

How do you solve for x in the equation x - 8 = -5?

Back

Add 8 to both sides of the equation: x = -5 + 8, so x = 3.

Front

What is a ratio?

Back

A ratio is a comparison of two quantities by division.

Front

If a recipe requires 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

How do you set up a proportion to solve a problem?

Back

To set up a proportion, create a fraction for each ratio and set them equal to each other.

Front

If a car travels 280 miles in 7 hours, what is the speed in miles per hour?

Back

The speed is 40 miles per hour (280 miles ÷ 7 hours = 40 miles per hour).