Alonzo plans to retire as soon as he has accumulated $250,000 through quarterly payments of $5,000. If Alonzo invests this money at 5.4% interest, compounded quarterly, how long (to the nearest year) until can he retire?

User Icon for Reiny Reiny answered
5 years ago

quarterly payment = 5000

i = .054/4 = .0135
n = ?
Amount = 250000

5000(1.0135^n - 1)/.01535 = 250000
1.0135^n - 1 = .0135(50000) = .675
1.0135^n = 1.675
take log of both sides and use log rules
n log 1.0135 = log 1.675
n = 38.47 quarter years or appr 9 years and 7 months

User Icon for Step-by-Step Bot Step-by-Step Bot answered
1 year ago

To find out how long it will take for Alonzo to retire, we can use the future value formula for compound interest:

FV = P * (1 + r/n)^(nt)

Where:
FV = Future Value (amount Alonzo wants to accumulate, $250,000)
P = Payment made every quarter ($5,000)
r = Interest rate (5.4%, or 0.054)
n = Number of times the interest is compounded per year (4 times, as there are 4 quarters in a year)
t = Number of years

Plugging in the values we have:

250000 = 5000 * (1 + 0.054/4)^(4t)

Simplifying the equation:

(1 + 0.054/4)^(4t) = 250000/5000
(1 + 0.0135)^(4t) = 50

Now, we can solve for t by taking the logarithm of both sides of the equation:

4t * log(1.0135) = log(50)
t = log(50) / (4 * log(1.0135))

Using a calculator, we find:
t ≈ 19.875

Therefore, it will take Alonzo approximately 19.875 years to retire. Rounded to the nearest year, this is 20 years.

User Icon for Explain Bot Explain Bot answered
1 year ago

To determine how long it will take Alonzo to retire, we can use the future value of an annuity formula:

A = P * ((1 + r/n)^(nt) - 1) / (r/n)

Where:
A = accumulated value (target amount)
P = payment per period
r = interest rate
n = number of compounding periods per year
t = number of years

In this case, Alonzo plans to accumulate $250,000, with quarterly payments of $5,000. The interest rate is 5.4%, compounded quarterly.

Let's plug in the values into the formula:

250,000 = 5,000 * ((1 + 0.054/4)^(4t) - 1) / (0.054/4)

Simplifying further:

(1 + 0.054/4)^(4t) - 1 = 250,000 * (0.054/4) / 5,000

Now, we can solve for t using logarithms.

(1 + 0.054/4)^(4t) = (250,000 * (0.054/4) / 5,000) + 1

Taking the natural logarithm on both sides:

ln((1 + 0.054/4)^(4t)) = ln((250,000 * (0.054/4) / 5,000) + 1)

Now, we can bring the exponent down:

(4t) * ln(1 + 0.054/4) = ln((250,000 * (0.054/4) / 5,000) + 1)

Finally, solving for t:

t = ln((250,000 * (0.054/4) / 5,000) + 1) / (4 * ln(1 + 0.054/4))

Using a calculator, we can find the value of t to the nearest year.