|  | 
| 
 
 
| Question 1209277:  A man makes a deposit of $50,000 into an account that pays an annual interest of 5%. How much money will be in the account after 10 years if:
 I. The interest is compounded continuously
 II. How long will it take for the money to triple itself if interest is compounded continuously?
 Answer by math_tutor2020(3817)
      (Show Source): 
You can put this solution on YOUR website! Part I
 
 P = 50000 = deposit amount
 e = special constant 2.718 approximately
 r = 0.05 = decimal form of the interest rate
 t = 10 years
 
 A = P*e^(r*t)
 A = 50000*e^(0.05*10)
 A = 82436.06353501
 A = 82436.06
 
 --------------------------------------------------------------------------
 
 Part II
 
 The man deposits P dollars and wants it to triple to 3P dollars.
 You could use P = 50,000 from earlier, but this also works for any positive real number.
 
 The r value is the same as before.
 The goal is to solve for variable t.
 
 A = P*e^(r*t)
 3P = P*e^(0.05*t)
 3 = e^(0.05*t)
 Ln(3) = Ln( e^(0.05*t) )
 Ln(3) = 0.05*t*Ln( e )
 Ln(3) = 0.05*t*1
 Ln(3) = 0.05*t
 t = Ln(3)/0.05
 t = 21.972246
 
 --------------------------------------------------------------------------
 
 Answers:
 I.  $82,436.06
 II.  21.972246 years approximately
 
 | 
  
 | 
 |  |  |