Calculate How Long Your Money Was in the Bank

Explanation:

To calculate the amount of time it takes for your money to reach $28,000 with an interest rate of 6% compounded continuously, we can use the continuous compounding formula:

A = P * e^(rt)

Where:

A is the final amount of money, which is $28,000

P is the principal balance, which is $20,000

e is the mathematical constant approximately equal to 2.71828

r is the interest rate per year, which is 6% or 0.06 as a decimal

t is the time in years that the money is left in the bank and needs to be calculated

Substituting the given values, we get:

$28,000 = $20,000 * e^(0.06t)

To solve for t, we can divide both sides of the equation by $20,000 and then take the natural logarithm of both sides:

ln($28,000/$20,000) = 0.06t

t = ln(1.4) / 0.06 ≈ 7.578 years

Rounding to the nearest tenth, the answer is D) 7.6 years.