Chapter 2, Working with percents, ratios, and proportions. This chapter continues the math review by introducing percents, ratios, and proportions as well cross-multiplication and means and extremes. The concepts of ratio strengths and strengths of mixtures are also introduced. | McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Math for the Pharmacy Technician: Concepts and Calculations Chapter 2: Percents, Ratios, and Proportions Egler • Booth McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Percents, Ratios, and Proportions 2- 2- McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Learning Outcomes Calculate equivalent measurements, using percents, ratios, decimals, and fractions. Indicate solution strengths by using percents and ratios. When you have successfully completed Chapter 2, you will have mastered skills to be able to: 2- McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Learning Outcomes Explain the concept of proportion. Calculate missing values in proportions by using ratios (means and extremes) and fractions (cross-multiplying). 2- McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Working with Percents . | McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Math for the Pharmacy Technician: Concepts and Calculations Chapter 2: Percents, Ratios, and Proportions Egler • Booth McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Percents, Ratios, and Proportions 2- 2- McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Learning Outcomes Calculate equivalent measurements, using percents, ratios, decimals, and fractions. Indicate solution strengths by using percents and ratios. When you have successfully completed Chapter 2, you will have mastered skills to be able to: 2- McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Learning Outcomes Explain the concept of proportion. Calculate missing values in proportions by using ratios (means and extremes) and fractions (cross-multiplying). 2- McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Working with Percents Provides a way to express the relationship of parts to a whole Indicated by symbol % Percent literally means “per 100” or “divided by 100” The whole is always 100 units/parts 2- McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Working with Percents (con’t) A number less than one is expressed as less than 100 percent A number greater than one is expressed as greater than 100 percent Any expression of one equals 100 percent = = 100 percent 2- McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Working with Percents Convert 42% to a decimal. Move the decimal point two places to the left Insert the zero before the decimal point for clarity 42% = 42.% = .42. = To convert a percent to a decimal, remove the percent symbol. Then divide the remaining number by 100. Example 2- McGraw-Hill ©2010 by the McGraw-Hill Companies, Inc All Rights Reserved Working with Percents (con’t) Convert to a percent. Multiply by 100% .
