SOLUTION: Just this year Mira decided to invest a total of 20,000 in an account that earns 5.2% interest compounded continuously. Mira is now 20 years old. Set up an equation determining the

Question 1110473: Just this year Mira decided to invest a total of 20,000 in an account that earns 5.2% interest compounded continuously. Mira is now 20 years old. Set up an equation determining the total money in the account at any time t in years. In what year will the principal double (in value)? How old is Mira by then?
Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
P=Poe^rt for continuous
P=20000*e^(0.052t) ANSWER
it will double in approximately 72/5.2 or about 14 years by rule of 72, which estimates it a little high.
40000=20000e^.052t
2=e^.052t
ln 2=.052t
0.693=0.052t
t=13.33 years
she will be 33
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