Percents 5.5. ACTIVITY: Writing Ratios. Percent. What is the connection between ratios, fractions, and percents?

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1 . Percents fractions, and percents? What is the connection between ratios, ACTIVITY: Writing Ratios Work with a partner. Write the fraction of the squares that are shaded. Write the ratio of the number of shaded squares to the total number of squares. How are the ratios and the fractions related? When can you write ratios as fractions? a. b. c. Percent A century is years. A cent is one hundredth of a dollar. In Mexico, a centavo is one hundredth of a peso. COMMON CORE Percents In this lesson, you will write percents as fractions with denominators of. write fractions as percents. Learning Standard 6.RP.c Cent means one hundred, so percent means per one hundred. The symbol for percent is %. 8 Chapter Ratios and Rates

2 ACTIVITY: Writing Percents as Fractions Work with a partner. What percent of each diagram in Activity is shaded? What percent of each diagram below is shaded? Write each percent as a fraction in simplest form. a. b. c. ACTIVITY: Writing Fractions as Percents Work with a partner. Draw a model to represent the fraction. How can you write the fraction as a percent? a. = = % Math Practice Consider Similar Problems How is this problem similar to ones you have seen before? How does this help you find the solution? b. d. 7 0 c. e.. IN YOUR OWN WORDS What is the connection between ratios, fractions, and percents? Give an example with your answer.. REASONING Your score on a test is 0%. What does this mean? Use what you learned about percents to complete Exercises 7 on page. Section. Percents 9

3 . Lesson Lesson Tutorials Key Vocabulary percent, p. Writing Percents as Fractions Words A percent is a part-to-whole ratio where the whole is. So, you can write a percent as a fraction with a denominator of. Numbers 60% = 60 out of = 60 n Algebra n% = part per one hundred (whole) EXAMPLE Writing Percents as Fractions Study Tip Equivalent fractions and percents represent the same number using different notations. a. Write % as a fraction in simplest form. % = = 7 So, % = 7. b. Write % as a fraction in simplest form. % = Write as a fraction with a denominator of. Simplify. Write as a fraction with a denominator of. = Simplify. So, % =. c. Write 7% as a mixed number in simplest form. 7% = 7 Write as a fraction with a denominator of. = 87, or 7 Simplify. So, 7% = 7. Exercises 8 9 Write the percent as a fraction or mixed number in simplest form.. %. 68%. 6%. 8% Chapter Ratios and Rates

4 Writing Fractions as Percents Words Write an equivalent fraction with a denominator of. Then write the numerator with the percent symbol. Numbers = = % EXAMPLE Writing a Fraction as a Percent Write as a percent. = Because =, multiply the numerator 6 = 6% and denominator by. Write the numerator with a percent symbol. EXAMPLE Midwestern United States Real-Life Application A drought affects 9 out of midwestern states. What percent of the midwestern states are affected by the drought? 9 = = 7 Simplify. = 7 = 7% Write the numerator with a percent symbol. So, 7% of the midwestern states are affected by the drought. Exercises 8 Write the fraction or mixed number as a percent WHAT IF? In Example, it rains in all the midwestern states. In what percent of the states affected by drought does it rain? Section. Percents

5 . Exercises Help with Homework. WRITING Explain how you can use a 0-by-0 grid to model %.. WHICH ONE DOESN T BELONG? Which one does not have the same value as the other three? Explain your reasoning. 0 0% OPEN-ENDED Write three different fractions that are less than 0%.. NUMBER SENSE Can be written as a percent? Explain. 9+(-6)= +(-)= +(-9)= 9+(-)= Use a 0-by-0 grid to model the percent.. 0% 6. % 7. % Write the percent as a fraction or mixed number in simplest form. 8. % 9. 90% 0. %. 7%. %. 79%. 77.%. 88% 6. 8% 7. % 8. 0.% 9. 0.%. ERROR ANALYSIS Describe and correct the error in writing % as a fraction. Write the fraction or mixed number as a percent. % = 0 = ERROR ANALYSIS Describe and correct the error in writing as a percent. = = 6 = 0.6% 0. LEFT-HANDED Of the students in your class, % are left-handed. What fraction of the students are left-handed? Are there more right-handed or left-handed students? Explain.. ARCADE You have % of the tickets required for a souvenir. What fraction of the required tickets do you have? Do you need more tickets for the souvenir? Explain. Chapter Ratios and Rates

6 Find the percent.. is what percent of 8?. is what percent of 6?. 9 is what percent of 6?. is what percent of 0? 6. SOCIAL NETWORKING A survey asked students to choose their favorite social networking website. The results are shown in the table. a. What fraction of the students chose Website A? b. What percent of the students chose Website C? Social Networking Website Number of Students Website A Website B Website C Website D 0 7. GEOGRAPHY The percent of the total area of the United States that is in each of four states is shown. Alaska Florida Hawaii Illinois 7.%.7% 0.88%.% a. Write the percents as fractions in simplest form. b. How many times larger is Illinois than Hawaii? c. Compared to the map of Florida, is the map of Alaska the correct size? Explain your reasoning. d. RESEARCH Which of the states are larger than Illinois? 8. CRITICAL THINKING A school fundraiser raised % of its goal last year and % of its goal this year. Did the fundraiser raise more money this year? Explain your reasoning. 9. CRITICAL THINKING How can you use a 0-by-0 grid to model %? 0. Write as a percent. Explain how you found your answer. Divide. Write the answer in simplest form. (Section.) MULTIPLE CHOICE Which of the following is not equal to? (Section.) A B 9 7 C 7 D 8 7 Section. Percents