The Mathematics of Money

(Darren Dugan) #1

C. Comparing Compounding Frequencies



  1. Complete the following table comparing the future value of $1,600 at 9% interest in 20 years, using different
    compounding frequencies.


Frequency Times/Year i n Formula

Future
Value
Annual
Semiannually
Quarterly
Monthly
Daily (bankers’
rule)
Daily (exact
method)

D. Continuous Compounding (Optional)



  1. Xiaoyi has deposited $2,199.50 in a 2-year CD paying 4.84% compounded continuously. How much will this account
    be worth at the end of its term?

  2. How much should I invest in order to have $5,000 at the end of 3 years if my account will earn 5.4% compounded
    continuously?

  3. Tessa deposited $1,056.25 in a 4-year CD paying 6.01% compounded daily. How much more interest would she earn if
    the CD paid the same rate compounded continuously?

  4. Suppose that you borrowed $850 at 11.3% compound interest for 5 years, but don’t remember how often the interest
    compounds. What is the largest amount you could possibly need to pay off the loan at maturity?


E. Compound Interest With “Messy” Terms



  1. Find the future value of the given amount of money, assuming interest compounds at the stated interest rate and
    compounding frequency for the given period of time.


a. $1,300 at 6.6% compounded monthly for 3½ years
b. $2,125 at 9.25% compounded quarterly for 5¾ years
c. $913.75 at 4% compounded daily (bankers’ rule) for 4½ years
d. $4,000 at 10.09% compounded monthly for 7 years and 5 months
e. $6,925.35 at 5½% compounded monthly for 63 months
f. $1,115.79 at 2^3 ⁄ 8 % compounded daily (bankers’ rule) for 4 years, 7 months, and 15 days.
g. $75,050.95 at 3.85% compounded daily (bankers’ rule) for 19 years, 2 months, and 28 days
h. $3,754.77 at 4.31% compounded daily (exact method) for 535 days


  1. How much interest would you earn from a $4,200 deposit in 30 months if the interest rate is 5.64% compounded monthly?


112 Chapter 3 Compound Interest

Free download pdf