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How long does it take for an investment of $4,800 to increase to $12,000 if it is invested at 8% per year compounded continuously? Round to the nearest tenth of a year

User Noxxys
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1 Answer

20 votes
20 votes

Answer;

11.9 years

Explanations:

The formula for calculating the compound amount is expressed as:


A=P(1+r)^t

where:

• P is the ,amount invested

,

• r is the r,ate

,

• t is the ,time taken

Given the following parameters

P = $4,800

A = $12,000

r = 8% = 0.08

Substitute


\begin{gathered} 12,000=4800(1+0.08)^t \\ (12000)/(4800)=1.08^t \\ 2.5=1.08^t \\ ln2.5=tln(1.08) \\ t=(ln2.5)/(ln1.08) \end{gathered}

Simplify to determine the value of t


\begin{gathered} t=(0.9163)/(0.07696) \\ t\approx11.9years \end{gathered}

Hence the time it will take for an investment of $4,800 to increase to $12,000 if it is invested at 8% per year compounded continuously is 11.9 years

User Paul Bambury
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