## Reflection: Modeling A Percent Equation - Section 1: Introduction

The "what percent" problems always cause a bit of difficult for many of my students.  The can easily find the part using the equation.  They can also find the whole using the equation.  Finding the percent using the equation is trickier.  I think it is because when you have solved the equation you are left with a part-whole ratio like 9.5 / 20.  Students needed to understand that this is another representation of a percent.  Once I point this out, the difficulties go away quickly.  Most students see that they can write 9.5 / 20 as 47.5 / 100 or 47.5%.

In my everyday life, I probably would go straight to the ratio when trying to decide 9.5 is what percent of 20.  I might even tell this to my students.  But the point of this lesson is for students to be well versed in using a simple equation to solve percent problems.

9.5 is what percent of 25? What?
Modeling: 9.5 is what percent of 25? What?

# A Percent Equation

Unit 5: Percent and Proportional Relationships
Lesson 10 of 15

## Big Idea: Solve 3 types of percent problems using 1 equation!

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Standards:
Subject(s):
Math, Number Sense and Operations, Percentages, equation, percent equation, what percent
50 minutes

### Grant Harris

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