Proportion 5 - Word Problems/Setting a proportion

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 for a word problem?

Back

Identify the two quantities being compared, write them as a ratio, and set them equal to each other.

Front

What does cross-multiplication mean in solving proportions?

Back

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

Front

If 1 CM on a map represents 50 miles, how do you find the actual distance for 3.5 CM?

Back

Set up the proportion: 1 CM/50 Miles = 3.5 CM/X Miles, then cross-multiply to solve for X.

Front

How many inches are in 2 feet?

Back

24 inches.

Front

If 3 gallons of gas allow you to travel 96 miles, how do you find the gallons needed for 160 miles?

Back

Set up the proportion: 3 gallons/96 miles = X gallons/160 miles, then cross-multiply to solve for X.

Front

What is the first step in solving a word problem involving proportions?

Back

Identify the quantities involved and determine the relationship between them.

Front

How do you convert feet to inches?

Back

Multiply the number of feet by 12, since there are 12 inches in a foot.

Front

What is the formula for finding the unknown in a proportion?

Back

If a/b = c/d, then ad = bc.

Front

If you can run 250 feet in 2.5 minutes, how do you find the distance in 7.5 minutes?

Back

Set up the proportion: 250 feet/2.5 minutes = X feet/7.5 minutes, then cross-multiply to solve for X.