SOLUTION: If the cost was $20 in 1998 and $40 in 2008, then what is the average rate of change of the cost for that time period?

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Question 1001297: If the cost was $20 in 1998 and $40 in 2008, then what is the average rate of change of the cost for that time period?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
It doubles in 10 years
p=Poe^rt
p/Po=2
2=e^rt
ln of both sides, t=10
0,0693=10r
r=6.93%. It is an interest problem with continuous compounding,