Modeling with Exponential Functions

is it a growth factor or a decay factor?

• Growth Factor

• Decay Factor

The original value of a painting is $1400, and the value increases by 9% each year. Write an exponential growth function to model this situation.

• y=1400(1.09)^x

• y=1.09(1400)^x

• y=1400(.91)^x

• y=1.09^x

Mr. Savage has $8,000,000 in his bank account, which accrues 1.932% interest every 3 months. How much money will be in his bank account after 9 years?

A rubber ball dropped on a small surface takes a sequence of bounces. Each bounce is half as high as the preceding one. If the ball is dropped from a height of 64 feet, determine the exponential decay equation to model the situation.

A rubber ball dropped on a small surface takes a sequence of bounces. Each bounce is half as high as the preceding one. If the ball is dropped from a height of 64 feet, determine the height of the ball after it hits the surface on the 5th bounce

• 486 feet

• 2 inches

• 2 feet

• 49.5 feet

Your dad buys a rare quitar in 2015 for $10,000. Experts estimate that its value will increase 12% per year. Use the given graph to predict approximately how many years it will take for the initial value to double.

• 4 years

• 5 years

• 6 years

• 7 years

A new car depreciates about 15% each year. You purchase a new car for $35,000. Using the graph predict about how many years it will take for the value of the care to be $25,000.

• 7 years

• 5 years

• 2 years

• 1 year

The foundation of your house has about 1,200 termites. The termites grow at a rate of about 2.4% per day. How long until the number of termites doubles?

• 29 to 30 days

• 23 to 24 days

• 15 to 16 days

• 19 to 20 days

The population of Bloom Falls, Mass. (population 937) is slowly moving to a bigger city.
Every year the population drops by 4.5%. What is the population after 3 years?

• 1,069 people

• 894 people

• 816 people

• 854 people

Classify the model as Exponential GROWTH or DECAY and identify the Growth or Decay factor .

• Growth of 15 %

• Decay of 15 %

• Growth of 85 %

• Decay of 85 %