Sandy is tracking the performance of one of Atlantic Cycles

Sandy is tracking the performance of one of Atlantic Cycles’ savings accounts. $20,000 was deposited into this account, which earns 1.25% interest, compounded continuously.

How many years will it take until the account balance doubles, if no withdrawals or additional deposits are made?

Solution

A = P(1+r/100)^t

P = 20000 $

r = 1.25%

A= 2*20000 = 40000

40000 = 20000 (1+0.0125)^t

40000/20000 = 1.0125^t

2 = 1.0125^t

log 2 = t log 1.0125

t = 56 years