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 terms and then solve for the unknown variable.

Front

If 4 pages take 18 minutes, how do you find the time for 30 pages?

Back

Set up the proportion: 4/18 = 30/x, then cross-multiply and solve for x.

Front

What is the unit rate?

Back

The unit rate is a comparison of two different quantities when they are combined together, expressed as a quantity per one unit.

Front

How do you find the cost per apple if 50 apples cost $25?

Back

Divide the total cost by the number of apples: $25/50 = $0.50 per apple.

Front

If Nathan packs 39 boxes in 3 hours, how do you find boxes per hour?

Back

Divide the total boxes by the total hours: 39 boxes / 3 hours = 13 boxes per hour.

Front

What is the formula for finding the total number of boxes packed in a shift?

Back

Total boxes = boxes per hour × total hours.

Front

How do you set up an equation to solve for x in a proportion?

Back

Use the form a/b = c/d, then cross-multiply to get ad = bc.

Front

What does it mean to cross-multiply?

Back

Cross-multiplying means multiplying the numerator of one fraction by the denominator of the other fraction.

Front

If 75 apples cost x dollars, how do you find x if 50 apples cost $25?

Back

Set up the proportion: 50/25 = 75/x, then cross-multiply and solve for x.