Lesson 3.3: Represent and Use the Percent Equation

Lesson 3.3

Represent and Use the Percent Equation

Definition:

Percent Equation: Percentages of numbers can be represented by using the following equation.

Part = Percent X Whole

Ex: Find 5% of 100

Part = 0.05 X 100

= 5

Key Concept:

In this lesson, we will use what we know about proportional reasoning to find percentages of numbers. We will use the percent equation to represent real world scenarios.

​Solve the problems using the percent equation:

​1. Find 25% of 400

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.

.

.

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2. 37 out of 40 is what percent?

Multiple Choice

Write a percent equation for 63% of 50.

• Part = 63 X 50

• 50 = 0.63 X Whole

• Part = 0.63 X 50

• 50 = 63 X Whole

Multiple Choice

Find 63% of 50.

• 3,150

• 1.26

• 31.5

• 0.79

​Example: A shirt that normally costs $30 is on sale for $21.75. What percent of the regular price is the sales price?

Multiple Choice

A shirt that normally costs $40 is on sale for $22. What percent of the regular price is the sales price?

• 0.55%

• 55%

• 181%

• 1.81%

​Example: Maria is trying to decide which one of two winter coats she should buy. The blue coat usually costs $48 but is on sale for 25% off. The black coat usually costs $56 but is on sale for 40% off. How much less is the sale price of the black coat than the sale price of the blue coat?

​Example: A garment is on sale for 35% off the regular price. If the garment normally sells for $48.80, what is the sales price?

Multiple Choice

A shirt is on sale for 25% off. If the shirt is usually $40, what is the sales price now?

• $10

• $30

• $1,000

• $160

​Conclusion: Write two complete sentences about what you learned.