Final answer:
Micaela would need an interest rate of approximately 3.9%, compounded continuously, to grow her investment from $46,000 to $73,000 in 16 years.
Step-by-step explanation:
To determine the interest rate required for Micaela's investment of $46,000 to grow to $73,000 in 16 years with compound interest being compounded continuously, we use the formula for continuous compounding A = Pert, 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).
- t is the time the money is invested or borrowed for, in years.
- e is the base of the natural logarithm.
Given:
- A = $73,000
- P = $46,000
- t = 16 years
We need to find r. Rearranging the formula to solve for r gives:
r = (1/t) * ln(A/P)
Calculating the value,
r = (1/16) * ln(73,000/46,000)
r ≈ 0.039 or 3.9% (to the nearest hundredth of a percent)
Micaela would need an interest rate of approximately 3.9% compounded continuously to reach her goal.