Download presentation
Presentation is loading. Please wait.
Published byGodfrey Chandler Modified over 8 years ago
1
Delgado Adult Education Percents Unit This unit will explain how percents relate to fractions and decimals, and how to solve percents word problems.
2
What do percents mean? What do they represent? Percents express a portion of a whole, just as fractions do. In fact, any fraction can be expressed as a percent, and vice versa. For instance, of the group of letters below, ¾ are d’s. 75% are d’s. d d g d Click on the following links for a Khan Academy videos about percents: https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-ratios-prop- topic/cc-6th-percentages/v/describing-the-meaning-of-percent Click on the following links for a Math is Fun lesson about percents. (Try some of the exercises at the bottom of the page. The rest of this unit will help you learn how to find percents, so if you find these exercises confusing, continue to the next slides and return to this page later.) http://www.mathsisfun.com/percentage.html
3
Converting fractions to percents Do you remember how to convert a fraction to a percent? It involves converting it into a decimal, and moving the decimal point. For instance, to convert ¾ into a percent, you begin by dividing 3 by 4: 3 ÷ 4 =.75 When you are dividing, go to the thousandth’s place, and if it doesn’t end without a remainder at that point, round to the nearest hundredth. Move the decimal point two spaces to the right, and add a percent symbol..75 -------> 75% Please click on the following link to watch a live demonstration: https://www.khanacademy.org/math/arithmetic/decimals/decimal_to _fraction/v/converting-fractions-to-decimals
4
Converting fractions to decimals, continued Convert the following fractions to percents: 2/3 5/6 1/3 1/4 1/5 1/6 Don’t flip to the next slide until you’re done!
5
Answers to the exercises on the previous page: 2/3 = 2 ÷ 3 =.666 (repeating) =.67 = 67% 5/6 = 5 ÷ 6 =.833 (repeating) =.83 = 83% 1/3 = 1 ÷ 3 =.333 (repeating) =.33 = 33% ¼ = 25% 1/5 = 20% 1/6 = 17% Click on this link for more exercises: http://www.mathsisfun.com/converting-fractions- percents.html
6
Finding percents In the previous pages, we learned how to convert a fraction to a decimal, and a decimal to a percent. This is one way to find a percent. The following Khan Academy videos will show you a second way to find a percent, and this other method will be an invaluable tool when solving percent problems. https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-ratios-prop- topic/cc-6th-percentages/v/finding-percentages-example https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-ratios-prop- topic/cc-6th-percentages/v/percent-word-problems Now try some exercises! https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-ratios-prop- topic/cc-6th-percentages/e/finding_percents
7
Percents Word Problems The key to solving percents problems is to know what information you’ve been given, and what you are looking for. The following lesson, written by a fellow teacher, will show you how to set up a percent problem as a proportion problem. Using the Proportion Method to Solve Percent Problems There are a variety of ways to solve percent problems, many of which can be VERY confusing. Fortunately, the PROPORTION METHOD will work for all three types of questions: What number is 75% of 4? 3 is what percent of 4? 75% of what number is 3? AS YOU WILL SEE ON THE NEXT PAGE, A PROPORTION IS A RELATIONSHIP BETWEEN TWO RATIOS, OR FRACTIONS. For instance: 1/25 = 2/50
8
This is the equation we will use to solve different types of percents problems. A proportion has four terms, and you will always be given three terms and asked to solve for the fourth term. At the bottom of the page, you will see the words and symbols that signal what terms the problem is giving you, and which term you are being asked to solve for. Learn and memorize these well!
9
Finding the part:
10
Finding the percent:
11
Finding the whole:
12
Practice exercises: Click the following link and scroll to the bottom of the page for additional exercises. http://amby.com/educate/math/4-2_prop.html You may also want to revisit the Math is Fun website and try some exercises: http://www.mathsisfun.com/percentage.html …After this, you will move on to solving other types of problems by using proportion equations and cross-multiplication. You can begin this unit by opening the proportions power-point under Math Lessons on our class website. KUDOS for completing this unit and getting on to the next!
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.