Proportions Classwork

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 variable.

Front

If a train travels 300 miles in 5 hours, what is its speed in miles per hour?

Back

Speed = Distance/Time = 300 miles / 5 hours = 60 miles per hour.

Front

If a car travels 420 miles in 8 hours, how far will it travel in 12 hours at the same speed?

Back

Distance = Speed x Time. Speed = 420 miles / 8 hours = 52.5 miles per hour. Distance in 12 hours = 52.5 miles/hour x 12 hours = 630 miles.

Front

What is the formula for finding a missing value in a proportion?

Back

Front

What does it mean if two ratios are equivalent?

Back

It means that they represent the same relationship between quantities.

Front

Back

y = 6.5.

Front

Back

n = 23.

Front

Back

x = 2.75.

Front

What is the cross-multiplication method?

Back

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