If $2,000 is invested at 4% annual interest compounded quarterly, how long would it take for the account balance to reach $10,000? Round your answer to the nearest tenth.

Respuesta :

Answer:

13.2 years

Step-by-step explanation:

To find out how long it would take for the account balance to reach $10,000, we can use the formula for compound interest:

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

Where:

A = the final account balance ($10,000)

P = the initial investment ($2,000)

r = the annual interest rate (4% or 0.04)

n = the number of times interest is compounded per year (quarterly, so n = 4)

t = the number of years we want to find

Let's substitute these values into the formula:

$10,000 = $2,000(1 + 0.04/4)^(4t)

Now, let's solve for t.

Divide both sides of the equation by $2,000:

5 = (1 + 0.01)^(4t)

Take the logarithm of both sides (base doesn't matter):

log(5) = log[(1 + 0.01)^(4t)]

Use the power rule of logarithms to bring the exponent down:

log(5) = 4t * log(1 + 0.01)

Divide both sides of the equation by 4 * log(1 + 0.01):

t = log(5) / (4 * log(1 + 0.01))

Using a calculator, we find that t is approximately 13.2 years (rounded to the nearest tenth).

Therefore, it would take approximately 13.2 years for the account balance to reach $10,000 when $2,000 is invested at 4% annual interest compounded quarterly.