Answered

Suppose you have $12,000 to invest. Which of the two rates would yield the larger amount in 4 years: 12% compounded monthly or 11.94% compounded continuously?

A. 12% compounded monthly
B. 11.94% compounded continuously



Answer :

To determine which rate yields a larger amount after 4 years, we need to compare two different interest compounding methods: 12% compounded monthly and 11.94% compounded continuously.

Step 1: Calculate the amount with 12% compounded monthly

For interest compounded monthly, we use the formula for compound interest:
[tex]\[ A = P \left(1 + \frac{r}{n}\right)^{nt} \][/tex]

Where:
- [tex]\(P\)[/tex] is the principal amount ([tex]$12,000) - \(r\) is the annual nominal interest rate (12% or 0.12 as a decimal) - \(n\) is the number of times interest is compounded per year (12 for monthly compounding) - \(t\) is the time the money is invested for in years (4 years) Plugging in these values: \[ A = 12000 \left(1 + \frac{0.12}{12}\right)^{12 \times 4} \] Calculating inside the parentheses first: \[ 1 + \frac{0.12}{12} = 1 + 0.01 = 1.01 \] Now raise this value to the power of \(12 \times 4 = 48\): \[ 1.01^{48} \] The amount after 4 years with 12% compounded monthly is: \[ A = 12000 \times 1.01^{48} \approx 19346.71 \] Step 2: Calculate the amount with 11.94% compounded continuously For interest compounded continuously, we use the formula: \[ A = Pe^{rt} \] Where: - \(P\) is the principal amount ($[/tex]12,000)
- [tex]\(e\)[/tex] is the base of the natural logarithm (approximately 2.71828)
- [tex]\(r\)[/tex] is the annual nominal interest rate (11.94% or 0.1194 as a decimal)
- [tex]\(t\)[/tex] is the time the money is invested for in years (4 years)

Plugging in these values:
[tex]\[ A = 12000 \times e^{0.1194 \times 4} \][/tex]

First, calculate the exponent:
[tex]\[ 0.1194 \times 4 = 0.4776 \][/tex]

Then, raise [tex]\(e\)[/tex] to this exponent:
[tex]\[ e^{0.4776} \][/tex]

The amount after 4 years with 11.94% compounded continuously is:
[tex]\[ A = 12000 \times e^{0.4776} \approx 19346.41 \][/tex]

Comparison and Conclusion

- 12% compounded monthly yields approximately [tex]$19,346.71. - 11.94% compounded continuously yields approximately $[/tex]19,346.41.

When comparing the two amounts:
[tex]\[ 19346.71 > 19346.41 \][/tex]

Therefore, the 12% compounded monthly rate yields a larger amount after 4 years.

Answer: The 12% compounded monthly option yields the larger amount.