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You invest $4500 in an account at interest rate r, compounded continuously. find the time required for the amount to double and triple. r=0.0415

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Final answer:

To calculate the time required for an investment to double or triple at an interest rate of 4.15%, compounded continuously, use the formula A = Pe^(rt) and solve for 't.' It takes approximately 16.7 years to double and 26.7 years to triple the investment.

Step-by-step explanation:

To determine the time required for an investment to double or triple when compounded continuously, you can use the formula A = Pert, where A is the amount of money accumulated after n years, including interest, P is the principal amount (the initial amount of money), r is the annual interest rate (decimal), t is the time the money is invested for, and e is the base of the natural logarithm. Here, we want to find t when A is twice or three times the initial principal P with r = 0.0415.

Finding Time to Double

To double the investment, we set A to 2P, so the equation becomes:

2P = Pe0.0415t

Dividing both sides by P, we get:

2 = e0.0415t

Taking natural logarithms of both sides, we find:

ln(2) = 0.0415t

Therefore, the time required to double is:

t = ln(2) / 0.0415 ≈ 16.7 years

Finding Time to Triple

To triple the investment, we set A to 3P and follow a similar process:

3 = e0.0415t

ln(3) = 0.0415t

t = ln(3) / 0.0415 ≈ 26.7 years

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