Proportion Word Problems

Front

What is a proportion?

Back

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

Front

How do you set up a proportion from a word problem?

Back

Identify the two quantities being compared, write their ratios, and set them equal to each other.

Front

What is the cross-multiplication method in solving proportions?

Back

Cross-multiplication involves multiplying the numerator of one ratio by the denominator of the other ratio to find the unknown.

Front

If a recipe calls for 2 cups of sugar for every 5 cups of flour, what is the ratio of sugar to flour?

Back

The ratio of sugar to flour is 2:5.

Front

How do you find an unknown quantity in a proportion?

Back

Set up the proportion, cross-multiply, and solve for the unknown.

Front

What is the scale factor in a model?

Back

The scale factor is the ratio of the dimensions of the model to the dimensions of the actual object.

Front

If a model car is 3 inches wide and the actual car is 4 feet wide, what is the scale factor?

Back

The scale factor is 1:16 (3 inches to 48 inches).

Front

How do you convert units in proportion problems?

Back

Use conversion factors to change one unit to another before setting up the proportion.

Front

What is the relationship between ratios and proportions?

Back

Ratios compare two quantities, while proportions state that two ratios are equal.

Front

If 1 cup of sugar is needed for every 5 cups of flour, how much sugar is needed for 30 cups of flour?

Back

6 cups of sugar are needed.