Writing Exponential Decay Functions for Percent Decrease Situations

The video tutorial explains exponential growth and decay, focusing on how change factors greater than 1 indicate growth, while those between 0 and 1 indicate decay. It illustrates how growth factors double quantities and decay factors reduce them. The tutorial details calculating decay factors from percent decreases, using examples like population decline and car depreciation to demonstrate the process. It concludes with forming exponential decay equations to model these situations.

What is the term used for a change factor greater than 1 in exponential equations?

• Decay factor

• Growth factor

• Neutral factor

• Reduction factor

If a population decreases by 3%, what is the decay factor?

• 1.03

• 0.97

• 0.7

• 0.03

How is a 3% decrease in population represented in terms of hundredths?

• 3 hundredths are added

• 97 hundredths are subtracted

• 3 hundredths are subtracted

• 97 hundredths are added

What is the decay factor when a car's value depreciates by 15% annually?

• 0.75

• 1.15

• 0.15

• 0.85

Which equation represents the depreciation of a car valued at $20,000 with a 15% annual decrease?

• y = 20,000 * 1.85^x

• y = 20,000 * 0.15^x

• y = 20,000 * 0.85^x

• y = 20,000 * 1.15^x