Growth or Decay? Exponential growth Percent Rate of Change: 10 %
Practice makes perfect
Let's start by recalling the general formula of exponential growth and exponential decay functions.
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Exponential Growth & Exponential Decay [0.8em]
y=a(1+r)^t & y=a(1-r)^t
In both cases, a and r are positive numbers. For exponential decay, r is less than 1. Let's rewrite the given function to match one of the above formulas.
y=15(1.1)^t ⇔ y= 15(1+ 0.1)^t
Our function matches the format of exponential growth. Here a= 15 and r= 0.1. Let's move the decimal point two places to the right to write the rate of growth, also known as the percent of change, in percentage.
r=0.1 ⇔ r=10 %
