Putting it Together
(Teacher Copy)

Activity  10:  Research into Ratio

Students find representations of ratios in printed materials and conduct their own investigation regarding a ratio.  

To find examples of ratio in newspapers, magazines, and real-life situations.

Introduction:  Ratios are often used on the job.  Ask students if they know someone who uses ratio on the job and in what ways and how frequently that individual uses ratio and other mathematical concepts.  (A cook uses ratios to follow recipes, a salesperson uses ratios to calculate percentages and discounts, a nurse uses ratios to determine medication amounts needed, a carpenter uses ratios to find the size of boards needed, and so forth.)  Talk with students about types of graphical representations where ratio is involved (such as bar and circle graphs).

Part A

Answers will vary.

Part B

Answers will vary.

Closing Discussion

• Do all graphs represent ratios?  Yes.  Data on graphs stand in comparison to other numbers, such as a total number of people surveyed, and so forth.
• If a cook needs to make twice as much food as she or he usually does, is she or he using ratio?  Yes.  It is a 2:1 ratio.   Why is a recipe a ratio?  Because the ingredient amounts called for are relative to the number of servings that the recipe makes.
• The Always in Style clothing store is having a sale.  Everything in the store is 25% off.  How can this be written as a ratio?  Examples:  25 to 100, 25:100,  25/100,  25¢ to 100¢
• Why do you think newspapers such as USA Today use graphs rather than stating information using tables or other forms of ratios?  Information can be acquired more rapidly (at a glance), and some people can understand and/or retain information more readily when it is presented visually.