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EXAMPLE 1. Writing a Ratio in Different Ways. Music. In some school orchestras, all of the instruments are stringed: violins,violas, cellos, and double basses. How can you compare the numbers of instruments in the orchestra?. 8. 35. Violas. Total instruments. EXAMPLE 1.
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EXAMPLE 1 Writing a Ratio in Different Ways Music In some school orchestras, all of the instruments are stringed: violins,violas, cellos, and double basses. How can you compare the numbers of instruments in the orchestra?
8 35 Violas Total instruments EXAMPLE 1 Writing a Ratio in Different Ways In the orchestra shown above, 8 of the 35 instruments are violas. The ratio of the number of violas to the total number of instruments, , can be written as ,as 8 : 35, or as 8 to 35.
1 1 3 Double basses 3 1 = = = Cellos 6 2 3 2 1 The ratio is , or 1 to 2, so there is 1 double bass for every 2 cellos. ANSWER 1 2 EXAMPLE 2 Writing Ratios in Simplest Form Use the diagram below. Write the ratio of the number of double basses to the number of cellos in simplest form.
ANSWER ANSWER 18 8 , 18 : 35, 18to 35 35 3 , 8 : 3, 8 to 3 for Examples 1 and 2 GUIDED PRACTICE In Exercises 1 and 2, write the ratio in three ways. 1.violins to total instruments 2.violas to double basses
ANSWER 1 , 1 : 3, 1to3 3 for Examples 1 and 2 GUIDED PRACTICE 3.Write the ratio of cellos to violins in simplest form.
SOLUTION Think about the denominators of the two fractions. 5 4 5 20 = 60 15 15 4 ANSWER 5 20 = 15 60 EXAMPLE 3 Writing an Equivalent Ratio 5 ? Complete the statement to write equivalent ratios. = 15 60
SOLUTION Write each ratio as a decimal. Then compare the decimals. 7 3 Sofia: Mike: 7out of10 0.7 = 0.75 = = 10 4 ANSWER Because 0.75>0.7, Sofia has the better record. EXAMPLE 4 Comparing Ratios Using Decimals 3 Football Sofia completes of her passes. Mike completes 7 out of every 10 passes. Who has the better record? 4
2 20 5 ? 6. 4. = = 7 35 32 3 ? 15 5. = ? 50 10 20 5 2 35 7 = = ANSWER ANSWER = ANSWER 8 3 32 15 10 50 for Examples 3 and 4 GUIDED PRACTICE Copy and complete the statement.
5 3 4 ? 18out of30 2 : 4 ? 7 : 35 7. 8. 9. ? 20 5 10 3 5 2 4 7 = 18out of30 > < 5 20 4 10 35 for Examples 3 and 4 GUIDED PRACTICE Copy and complete the statement using <, >, or =.