1. Ratio and proportions Project A ratio buddy!
CCSS.6.RP.3: Use ratio (and rate) to solve real-world and mathematical problems
Be ready to learn: on your desk…pencil, notebook, measuring tools…
Essential Question: How could you use tables & quantities to find heights of trees?

2. Ratio buddy notices the length of his shadow at a certain time of day.

3. Find ratio buddy in the classroom
Find ratio buddy in the classroom. Measure his height and the length of his shadow using standard units of measure. Record the results of your measurements in your Journal on the provided worksheet.

4. Check the results of your measurements.
Ratio Buddy is 2 feet tall.
Ratio Buddy’s shadow is 6 feet long.

5. Discuss with your partners a method of solving this question
Discuss with your partners a method of solving this question. If a tree casts a shadow of 60 feet, how tall is the tree if it is the same time of day that ratio buddy sees his shadow and the shadows are proportional?
What is the height of the tree? “h”
Ratio Buddy is 2 feet tall.
The tree’s shadow is 60 feet long.
Ratio Buddy’s shadow is 6 feet long.

6. Discuss with your partners a method of solving this question
Discuss with your partners a method of solving this question. If a tree casts a shadow of 72 feet, how tall is the tree if it is the same time of day that ratio buddy sees his shadow and the shadows are proportional?
What is the height of the tree? “h”
Ratio Buddy is 2 feet tall.
The tree’s shadow is 60 feet long.
Ratio Buddy’s shadow is 6 feet long.

7. Ratio Buddy Chart Project A
Discuss how you solve these problems. Work on your notebook as it will be graded as project.
Could we easily find the height of any tree if we measured the length of the shadow and could measure the height of a shorter tree?
Let’s build a ratio table to show how to find the height of a tree
(having ratio buddy’s height and shadow length).
Length of shadow
of the tree 60 72 15
120
Height of tree 20 6

8. Practice
Complete the Ratio Buddy chart. (15 minutes)

9. Check your work. Discuss how your solved these problems.
Could we easily find the height of any tree if we measured the length of the shadow and could measure the height of a shorter tree?
Let’s build a ratio table to show how to find the height of a tree.
Length of shadows 60 18 72 15
120
Height of trees 20 6 24 5 40