Name: How Do You Use Growth Factor to Find the Initial Amount?
Uploaded: 2023-03-01T08:13:10.573Z
Channel: House of Math
Description: You can use a growth factor or decay factor to find an unknown initial amount. This video explains that process, and how to do the calculation.

You can use a growth factor or decay factor to find an unknown initial amount. This video explains that process, and how to do the calculation.

A growth factor helps you calculate a final amount after a percentage has been added or subtracted. It is given by the formula:

 is the decimal representation of the percentage that is being added or subtracted.

Indicates the percentage increase or decrease between the initial and final amounts. Also known as growth rate.

The starting amount, before a percentage increase or decrease

The amount after you have included the percentage increase or decrease. It is given by the formula:

A decay factor helps you calculate a final amount after a percentage has been subtracted. It is given by the formula:

 is the decimal representation of the percentage that is being subtracted.

Indicates the percentage decrease between the initial and final amounts. Also known as decay rate.

Mathagon

Growth Factor

Growth Factor for an Increase

Decay Factor

Decay Factor for a Decrease

Growth Factor Equal to 1

Finding the Initial Amount 

Finding a Percentage Increase

Finding a Percentage Decrease

Increasing by the Same Percentage Multiple Times

Decreasing by the Same Percentage Multiple Times

Growth Factors

You solve for the initial amount by using the growth factor and decay factor. This video explains how to find an unknown initial amount and how to calculate.