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 solve a proportion?

Back

To solve a proportion, cross-multiply the two ratios and then solve for the unknown.

Front

What does it mean to scale a quantity?

Back

Scaling a quantity means to increase or decrease it by a certain factor.

Front

If Sue types 3 pages in the same time Mary types 4.5 pages, how do you find out how many pages Mary types when Sue types 11 pages?

Back

Set up a proportion: 3/4.5 = 11/x, then cross-multiply and solve for x.

Front

What is the formula for finding the expected number of items in a population?

Back

Expected number = (part/whole) * total population.

Front

If 14 out of 50 fish are trout, how do you estimate the number of trout in a lake with a population of 7,500?

Back

Use the proportion: 14/50 = x/7500, then solve for x.

Front

What is a ratio?

Back

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

Front

How do you find the total number of homes with a computer if 13 out of 20 homes have one?

Back

Set up a proportion: 13/20 = x/60, then solve for x.

Front

What is cross-multiplication?

Back

Cross-multiplication is a method used to solve proportions by multiplying the numerator of one ratio by the denominator of the other.

Front

If a 6-ounce package has 45 pieces, how do you find the number of pieces in a 10-ounce package?

Back

Set up a proportion: 45/6 = x/10, then cross-multiply and solve for x.