Digits, Grade 7, Volume 1, Homework Helper

9-5: Percent Increase and Decrease

Key Concept

You can use a percent to describe how much something has increased or decreased.

A percent of change describes how much a quantity has changed, expressed as a percent of the original quantity.

The current height of the growing flower is the original height plus the increase in height.

table with 3 rows and 2 columns , row1 column 1 , part , column 2 equals . percent . middle dot , whole , row2 column 1 , amountofchange , column 2 equals . percentofchange . middle dot . originalquantity , row3 column 1 , percentofchange , column 2 equals . fraction amountofchange , over originalquantity end fraction , end table

When a quantity increases, the percent of change is called a percent increase.

The current height of a growing flower is 15 cm, which is its original height of 10 cm plus an increase in height of 5 cm.

table with 5 rows and 2 columns , row1 column 1 , percentofchange , column 2 equals . fraction amountofchange , over originalquantity end fraction , row2 column 1 , percentincrease , column 2 equals , 5 tenths , row3 column 1 , , column 2 equals , 1 half , row4 column 1 , , column 2 equals 0.5 , row5 column 1 , , column 2 equals 50 percent , end table

The height of the flower increased by 50%.


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Table of Contents

Digits, Grade 7, Volume 1, Homework Helper Unit A: Number and Operations Unit B: Expressions, Equations, and Relationships Unit C: Measurement and Geometry Unit D: Proportionality English/Spanish Glossary Formulas Math Symbols Formulas Measures Properties