Author: mark_cameron
Last saved by: MHE
Company: McGraw-Hill

Lesson 4-1
  
Example 1 Write Ratios in Simplest Form
Express 7 Schnauzers out of 21 dogs in simplest form.

Divide the numerator and denominator by the greatest common factor, 7. Divide out common units.

	
The ratio of Schnauzers to dogs is  or 1 out of 3.

Example 2 Write Ratios in Simplest Form
Express 6 inches to 1 foot in simplest form.

Convert 1 foot to 12 inches. 

Divide the numerator and the denominator by 6. Divide out common units.

	   = 			

The ratio in simplest form is  or 1:2.

Example 3 Find a Unit Rate
TRAVEL On a trip from Columbus, Ohio, to Cleveland, Ohio, Jon drove 144 miles in 2 hours. What was Jon’s average speed in miles per hour?

Write the rate that expresses the comparison of miles to hours. Then find the average speed by finding the unit rate.

Divide the numerator and denominator by 2 to
get a denominator of 1.

Jon drove an average speed of 72 miles per hour.

Example 4 Compare Unit Rates
SHOPPING Kelly spends $12.50 for 2 pounds of chocolate covered cherries and $15.75 for 3 pounds of fudge. Which item costs less per pound?

For each item, write a rate that compares the cost of the item to the number of pounds. 
Then find the unit rates.
Chocolate Covered Cherries:	
Fudge:	

The chocolate covered cherries cost $6.25 per pound, and the fudge costs $5.25 per pound. So, the fudge costs less per pound than the chocolate covered cherries.