# An initial population of 4 tribbles was brought aboard the Enterprise. They grow at a rate of 50% every hour. Write an exponential growth function for this scenario

Question
Functions
An initial population of 4 tribbles was brought aboard the Enterprise. They grow at a rate of 50% every hour. Write an exponential growth function for this scenario

2021-01-28
An exponential growth function is of the form $$\displaystyle{y}={a}{\left({b}\right)}^{{x}}$$ where aa is the initial amount and bb is the growth factor.
If the initial population is 4 tribbles, then a=4.
If the population is growing at a rate of 50% every hour, then the growth factor is b=100%+50%=150%=1.5.
The exponential growth function is then y=4(1.5)x.

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