1. Lesson 53: Ratio Word Problems Students will use ratio boxes to organize the data in ratio word problems Use proportions to solve ratio problems

2. Review of Ratios Ratio: a way to describe a relationship between numbers. Ratios can be written in 3 forms:  2:32 to 3  All of the forms can be read “two to three” Ex. If a team won three games and lost seven what was the team’s win-loss ratio? 3:7

3. Review of Proportions Proportions: a true statement that two ratios are equal. This is read as: “Three is to four as six is to eight”

4. NEW SKILL How do we use a given ratio to help us solve word problems? Use a RATIO BOX! RATIOACTUAL COUNT Item 1 Item 2

5. Ex. The ratio of boys to girls in a class was 5 to 4. If there were 8 girls in the class, how many boys were there? We can use 2 ratios and set up a proportion to solve for a missing variable. RATIOACTUAL COUNT Boys5b Girls48

6. RATIOACTUAL COUNT Boys5b Girls48 The constant factor is 2 (4 x 2 = 8) so there are 10 boys (5 x 2 = 10)

7. Practice Word Problems (1) The ratio of salamanders to frogs was 5 to 7. If there were 20 salamanders, how many frogs were there? RATIOACTUAL COUNT Salamanders520 Frogs7f = 28

8. The ratio of blue balloons to red at a Legacy party is 3 to 7. If there are a total of 39 blue balloons, how many are red? RATIOACTUAL COUNT Blue339 Red7g = 91