Ratios, Rates and Percents Lesson 1 Ratios, Rates and Percents Ratios

Warm-Up Simplify each fraction. Write your answer as a proper or improper fraction, not as a mixed number.

Target: Simplify and write ratios three ways.

Vocabulary Ratio: A comparison of two numbers using division.

Writing Ratios A ratio comparing two numbers, 3 and 5 can be written in three ways: As a fraction → Using a colon → 3:5 Using the word “to” → 3 to 5

Example 1a Fraction Colon “to” 4:3 4 to 3 Paul took a handful of jelly beans. He chose 4 blue, 2 green, 3 red and 3 yellow. Write a ratio using each of the three ways. Compare blue jelly beans to red jelly beans. Fraction Colon “to” 4:3 4 to 3

Example 1b Fraction Colon “to” 1:6 1 to 6 Paul took a handful of jelly beans. He chose 4 blue, 2 green, 3 red and 3 yellow. Write a ratio using each of the three ways. Compare green jelly beans to total number of jelly beans. Fraction Colon “to” 1:6 1 to 6

Example 1c Fraction Colon “to” 1:4 1 to 4 Paul took a handful of jelly beans. He chose 4 blue, 2 green, 3 red and 3 yellow. Write a ratio using each of the three ways. Compare red jelly beans to total number of jelly beans. Fraction Colon “to” 1:4 1 to 4

Example 2 The ratio of boys to girls on a soccer team is 8:7. What is the ratio of boys to all players on the soccer team? There are 8 boys for every 7 girls. For every 8 boys there are 7 + 8 = 15 players. The ratio of boys to all players is 8:15.

Exit Problems Simplify the ratio 100 : 20 and write the ratio as a fraction, with a colon, and using the word “to”.   Lucas had 6 red jelly beans and 9 purple jelly beans. Write each ratio as a fraction in simplest form. Write the ratio of the number of red jelly beans to the number of purple jelly beans. Write the ratio of the number of red jelly beans to the total number of jelly beans Lucas has.

Communication Prompt The ratio of boys to girls in math class is 1 : 2. What does this ratio mean?