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Tommy is planning for his retirement. He makes his first $2,000 deposit into an IRA earning 2.6% compounded annually on his 23rd birthday and his last $2,000 deposit on his 40th birthday (18 equal deposits in all). He then decides to leave the money in the account until he retires on his 65th birthday. How much is in the IRA when he retires? How much interest did he earn over the years?

User RMorrisey
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Answer:

Therefore, Tommy earned approximately $70,973.48 in interest over the years.

Explanation:

To find out how much is in the IRA when Tommy retires, we need to calculate the future value of the deposits he made.

First, let's calculate the future value of each deposit separately.

The formula to calculate the future value of a deposit compounded annually is:

FV = PV * (1 + r)^n

Where FV is the future value, PV is the present value (amount deposited), r is the annual interest rate, and n is the number of years the money is left in the account.

For the first deposit, PV = $2,000, r = 2.6% = 0.026, and n = 65 - 23 = 42 years.

FV1 = $2,000 * (1 + 0.026)^42

FV1 ≈ $6,180.95

For the last deposit, PV = $2,000, r = 2.6% = 0.026, and n = 65 - 40 = 25 years.

FV2 = $2,000 * (1 + 0.026)^25

FV2 ≈ $3,703.44

Now, let's calculate the future value of the annuity, which is the sum of all the individual deposit values.

The formula to calculate the future value of an annuity compounded annually is:

FV_annuity = A * [(1 + r)^n - 1] / r

Where FV_annuity is the future value of the annuity, A is the amount deposited each year (in this case $2,000), r is the annual interest rate, and n is the number of years the money is left in the account.

FVannuity = $2,000 * [(1 + 0.026)^42 - 1] / 0.026 FVannuity ≈ $97,089.09

Finally, to find out the total amount in the IRA when Tommy retires, we need to add the future value of the individual deposits to the future value of the annuity.

Total FV = FV1 + FV2 + FV_annuity

Total FV ≈ $6,180.95 + $3,703.44 + $97,089.09

Total FV ≈ $106,973.48

Therefore, there will be approximately $106,973.48 in the IRA when Tommy retires.

To calculate the interest earned over the years, we subtract the total amount of deposits made from the total amount in the IRA.

Interest earned = Total FV - Total deposits

Interest earned = $106,973.48 - (18 * $2,000)

Interest earned = $106,973.48 - $36,000

Interest earned = $70,973.48

Therefore, Tommy earned approximately $70,973.48 in interest over the years.

User Hesam Faridmehr
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