1. Ratios Using Data

2. Ratio is a comparison of two numbers, Usually written as a fraction a/b, where a and b are the numbers First number in the numerator Second number in the denominator Different ways to write a ratio: 3 to 4 3:4 ¾ 3 out of 4 All ratios should be in reduced form

3. Finding Ratios Bag Marbles 10 blue 15 yellow 3 green 1 purple 24 pink Ratio blue to yellow Ratio green to blue Ratio green to yellow Ratio purple to pink Ratio blue to pink Ratio purple to green Ratio yellow to green 10/15 = 2/3 3/ 10 3/15 = 1/5 1/24 10/24 = 5/12 1/3 15/3 = 5/1

4. Our Classroom Ratio of girls to boys Ratio of boys to girls Ratio of number students to teacher Ratio of girls to number of students Ratio of boys to number of students

5. Equal Ratios same as Equivalent fractions 12/15 = 4/524/30 = 4/5 10/16 = 5/824/48 = ½ 48/18 = 8/360/20 = 3/1 5/6 = 15/18 = 10/12 = 20/24 = 25/30 = 30/36

6. Write each ratio in simplest form 25/75110/20 12 to 44 15 : 40 1/311/2 3 to11 3:8

7. Comparing Ratios You can use a decimal to express and compare ratios ¾ =.75 5 to 16 =.3125 7:8 =.875 5/16 < ¾ < 7/8