Solving 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 then solve for the unknown.

Front

If a car travels 320 miles in 7.5 hours, what is its speed in miles per hour?

Back

Speed = Distance / Time = 320 miles / 7.5 hours = 42.67 miles per hour.

Front

What is the formula for direct variation?

Back

The formula for direct variation is y = kx, where k is the constant of variation.

Front

If a car travels 280 miles in 7 hours, what is the constant of variation?

Back

k = Distance / Time = 280 miles / 7 hours = 40 miles per hour.

Front

What is a ratio?

Back

A ratio is a comparison of two quantities by division.

Front

How do you simplify a ratio?

Back

To simplify a ratio, divide both terms by their greatest common factor.

Front

What is the simplified ratio of 60 yellow cards to 110 blue cards?

Back

Front

If 4 big water bottles hold 8 gallons, how much does 1 bottle hold?

Back

1 bottle holds 8 gallons / 4 = 2 gallons.

Front

How much water can 3 big water bottles hold if 1 holds 2 gallons?

Back

3 bottles hold 3 * 2 gallons = 6 gallons.