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John deposited $3000 into an account with a 7% annual interest rate, compounded quarterly. assuming that no withdrawals are made, how long will it take for the investment to grow to $4470 ? do not round any intermediate computations, and round your answer to the nearest hundredth.

User Korfu
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Final answer:

To find out how long it will take for an investment to grow to a certain amount with compound interest, we use the compound interest formula and solve for the time variable. In this case, it takes approximately 15.22 years for a $3,000 investment with a 7% annual interest rate compounded quarterly to grow to $4,470.

Step-by-step explanation:

To solve the mathematical problem of calculating the time it takes for an investment to grow from $3,000 to $4,470 at a 7% annual interest rate compounded quarterly, we can use the formula for compound interest:

A = P(1 + r/n)(nt)

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 (in decimal form).

n is the number of times that interest is compounded per year.

t is the time the money is invested for, in years.

We have:

A = $4,470

P = $3,000

r = 0.07 (7% in decimal form)

n = 4 (since compounded quarterly)

We need to find t and we can rearrange the formula to solve for t:

t = (log(A/P)) / (n*log(1 + r/n))

Substituting the given values, we get:

t = (log(4,470 / 3,000)) / (4 * log(1 + 0.07/4)

Calculating the values, we get:

t = (log(1.49)) / (4 * log(1.0175)

t ≈ 15.22

Therefore, it will take approximately 15.22 years for the investment to grow to $4,470.

User Poma
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