Question 68185:  Last week's profits from a dry cleaners was $2000. Suppose the $2000 is invested at interest rate k, compounded continuously, and grows to $2983.65 in 5 years.  
What is the interest rate?  
Find the exponential growth function.  
What will the balance be after 10 years?  
When will the $2,000 double? 
 
 Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! Last week's profits from a dry cleaners was $2000. Suppose the $2000 is invested at interest rate k, compounded continuously, and grows to $2983.65 in 5 years. 
Formul for continuously compounded investment: A=Pe^(rt) 
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What is the interest rate? 
2983.65=2000e^(5k) 
1.491825=e^(5k) 
Take the natural log of both sides to get: 
0.40=5k 
k=0.8 = 8% 
Interest rate is 8% 
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Cheers, 
Stan H
 
 
Find the exponential growth function.  
What will the balance be after 10 years?  
When will the $2,000 double?
 
 
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