Growth or Decay? Exponential decay Percent Rate of Change: 52 %
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]
s(t)=a(1+r)^t & s(t)=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.
s(t) = 0.65(0.48)^t
⇕
s(t)= 0.65(1- 0.52)^t
Our function matches the format of exponential decay. Here a= 0.65 and r= 0.52. We can express the rate of decay, also known as the percent of change, as a percent by moving the decimal point two places to the right.
r=0.52 ⇔ r=52 %
