Lesson 12: Percents and Tape Diagrams

1. Lesson 12: Percents and Tape Diagrams Essential Question: How can we represent percents visually to help us solve problems?

2. Let’s Discuss… How could a 10 x 10 square grid represent 200 people? Each square represents 2 people.

3. Let’s Discuss… How could a tape diagram represent 200 people? What is similar and different between the two visual models?

4. Remember… • Tape diagram segment divisions will vary depending upon the percent. • Example: • To find 20%, it is useful to divide 100 into 5 segments; to find 10%, it is useful to divide 100 into 10 segments, etc.

5. Complete the tape diagram. Shade in 25% on the tape diagram where the whole represents different amounts. What fraction is represented by the tape diagram? Express the quantity in the diagram as follows: 25% of ______ = _______

6. Complete the tape diagram. Shade in 25% on the tape diagram where the whole represents different amounts. What fraction is represented by the tape diagram? Express the quantity in the diagram as follows: 25% of ______ = _______

7. Complete the tape diagram. Shade in 25% on the tape diagram where the whole represents different amounts. What fraction is represented by the tape diagram? Express the quantity in the diagram as follows: 25% of ______ = _______

8. Complete the tape diagram. Shade in 25% on the tape diagram where the whole represents different amounts. What fraction is represented by the tape diagram? Express the quantity in the diagram as follows: 25% of ______ = _______

9. Complete the tape diagram. Shade in 25% on the tape diagram where the whole represents different amounts. What fraction is represented by the tape diagram? Express the quantity in the diagram as follows: 25% of ______ = _______

10. Partner Work • You will be given a percent: • (such as 10%, 20%, 50%, or 75%). • 2. With your partner, label the given tape diagrams in which you must find the assigned percent of the following wholes: • 100, 200, 60, 20, 500

11. What pattern can you see from the fractions represented by each tape diagram?What conclusion can be drawn? • All fractions are equivalent and equal to 25% or ¼. • 25% represents different quantities (depending upon the amount of the whole).

12. Let’s Review… • The quantity represented by a percent depends upon the size of the whole. • Visual representations of percents are useful in solving percent problems.

13. Ticket to Leave In your math journal/notebook, explain why 25% does not always represent the same amount.