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Example Question #1 : Growth And Decay
Stuff animals were a strange craze of the 90's. A Cat stuff animal with white paws sold for $6 in 1997. In 2015, the Cat will sell for $1015. What has been the approximate rate of growth for these stuff animal felines?
Use the formula for exponential growth where y is the current value, A is the initial value, r is the rate of growth, and t is time. Between 1997 and 2015, 18 years passed, so use . The stuffed animal was originally worth $6, so . It is now worth $1,015, so .
Our equation is now:
divide by 6:
take both sides to the power of :
As a percent, r is about 33%.