Suppose a machine will yield a net of $200 per month for 5 years, after which the machine
would be worthless. How much should the firm pay for the machine if it wants to earn 5%
annually on its investment and also set up a sinking fund to replace the purchase price?
For the fund, assume monthly payments and a rate of 4% annually.
Suppose that you want to invest some money in order to have $1000 available at some later
time. If you invest it at 7% interest compounded continuously, the amount you need to
invest now, P, is related to the number of years from now that you need the money, t, by:
P(t) = 1000e–0.07t. Graph this on your graphing calculator in the window 0,20 ×0,1000 .
Discuss the behavior of this graph.
Suppose you have the opportunity to invest $6000 in a business venture such that you will
be repaid $8000 in five years. On the other hand, you can put the $6000 in a savings
account that pays 5.25% compounded monthly. Which investment is better?
A person amortizes a loan of $180,000 for a new home by obtaining a 30–year mortgage at
the rate of 8.7% compounded monthly. Find (a) the monthly payment, (b) the total interest
charges, and (c) the principal remaining after 10 years.
Find the present value of an ordinary annuity with quarterly payments of $250 for 40 years
at 7.25% compounded quarterly.
Suppose you have the opportunity to invest $1000 in a business such that the value of your
investment after seven years will be $1500. On the other hand, you can put the $1000 into a
certificate of deposit that pays 6% compounded monthly. Which is better?
Find the future value of an ordinary annuity with quarterly payments of $300 for 30 years
at 7.5% compounded quarterly.
Find the future value of an annuity due with semiannual payments of $6,250 for 21 years at
4.25% compounded semiannually.