Question 425655
 How do I find the growth rate between 1980 and 1990 assuming exponential growth. If in 1980 it was 825 and in 1990 it was 2810?
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Form: y = ab^x
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Let "t" be the number of years after 1980.
Equations:
You have two point (0,825) and (10,2810)
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Substitute and solve for "a" and for "b":
2810 = ab^10
825  = ab^0
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Divide the lower into the higher eq. and solve for "b":
3.4061 = b^10
b = 3.4061^(1/10) =  1.1304
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Solve the lower equation for "a":
825 = a*1
a = 825
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Equation for your problem:
f(t) = 825*(1.1304)^t where "t" is the # of years after 1980
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Cheers,
Stan H.
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