Chapter 4
Applied Mathematics: For the Managerial, Life, and Social Sciences · 143 exercises
Problem 1
Find the periodic payment \(R\) required to amortize a loan of \(P\) dollars over \(t\) yr with interest charged at the rate of \(r \% /\) year compounded \(m\) times a year. $$ P=100,000, r=8, t=10, m=1 $$
8 step solution
Problem 1
Find the amount (future value) of each ordinary annuity. $$\$ 1000$$ /year for 10 yr at \(10 \% /\) year compounded annually
4 step solution
Problem 1
Find the accumulated amount \(A\) if the principal \(P\) is invested at the interest rate of \(r /\) year for \(t\) yr. $$ P=\$ 1000, r=7 \%, t=8, \text { compounded annually } $$
5 step solution
Problem 1
Find the simple interest on a $$\$ 500$$ investment made for 2 yr at an interest rate of \(8 \% /\) year. What is the accumulated amount?
5 step solution
Problem 2
Find the periodic payment \(R\) required to amortize a loan of \(P\) dollars over \(t\) yr with interest charged at the rate of \(r \% /\) year compounded \(m\) times a year. $$ P=40,000, r=3, t=15, m=2 $$
5 step solution
Problem 2
Find the amount (future value) of each ordinary annuity. $$\$ 1500 /$$ semiannual period for 8 yr at \(9 \%\) /year compounded semiannually
5 step solution
Problem 2
Find the simple interest on a $$\$ 1000$$ investment made for 3 yr at an interest rate of \(5 \% /\) year. What is the accumulated amount?
5 step solution
Problem 3
Find the periodic payment \(R\) required to amortize a loan of \(P\) dollars over \(t\) yr with interest charged at the rate of \(r \% /\) year compounded \(m\) times a year. $$ P=5000, r=4, t=3, m=4 $$
3 step solution
Problem 3
Find the amount (future value) of each ordinary annuity. $$ \text { \$1800/quarter for } 6 \text { yr at } 8 \% \text { year compounded quarterly } $$
3 step solution
Problem 3
Find the accumulated amount at the end of \(9 \mathrm{mo}\) on an $$\$ 800\( \)deposit in a bank paying simple interest at a rate of \(6 \% /\) year.
3 step solution
Problem 4
Find the periodic payment \(R\) required to amortize a loan of \(P\) dollars over \(t\) yr with interest charged at the rate of \(r \% /\) year compounded \(m\) times a year. $$ P=16,000, r=9, t=4, m=12 $$
5 step solution
Problem 4
Find the amount (future value) of each ordinary annuity. $$\$ 500 /$$ semiannual period for \(12 \mathrm{yr}\) at \(11 \% / \mathrm{year}\) compounded semiannually
3 step solution
Problem 4
Find the accumulated amount at the end of \(8 \mathrm{mo}\) on a $$\$ 1200$$ bank deposit paying simple interest at a rate of \(7 \% /\) year.
3 step solution
Problem 5
Find the periodic payment \(R\) required to amortize a loan of \(P\) dollars over \(t\) yr with interest charged at the rate of \(r \% /\) year compounded \(m\) times a year. $$ P=25,000, r=3, t=12, m=4 $$
5 step solution
Problem 5
Find the amount (future value) of each ordinary annuity. $$ \text { \$600/quarter for } 9 \text { yr at } 12 \% / \text { year compounded quarterly } $$
4 step solution
Problem 5
If the accumulated amount is $$\$ 1160$$ at the end of \(2 \mathrm{yr}\) and the simple rate of interest is \(8 \% /\) year, then what is the principal?
5 step solution
Problem 6
Find the periodic payment \(R\) required to amortize a loan of \(P\) dollars over \(t\) yr with interest charged at the rate of \(r \% /\) year compounded \(m\) times a year. $$ P=80,000, r=10.5, t=15, m=12 $$
4 step solution
Problem 6
Find the amount (future value) of each ordinary annuity. $$ \$ 150 / \text { month for } 15 \text { yr at } 10 \% / \text { year compounded monthly } $$
5 step solution
Problem 6
A bank deposit paying simple interest at the rate of \(5 \% /\) year grew to a sum of $$\$ 3100$$ in 10 mo. Find the principal.
4 step solution
Problem 7
Find the periodic payment \(R\) required to amortize a loan of \(P\) dollars over \(t\) yr with interest charged at the rate of \(r \% /\) year compounded \(m\) times a year. $$ P=80,000, r=10.5, t=30, m=12 $$
4 step solution
Problem 7
How many days will it take for a sum of $$\$ 1000$$ to earn $$\$ 20$$ interest if it is deposited in a bank paying ordinary simple interest at the rate of \(5 \% /\) year? (Use a 365 -day year.)
6 step solution
Problem 8
How many days will it take for a sum of $$\$ 1500$$ to earn $$\$ 25$$ interest if it is deposited in a bank paying \(5 \% /\) year? (Use a 365-day year.)
4 step solution
Problem 9
Find the periodic payment \(R\) required to accumulate a sum of \(S\) dollars over \(t\) yr with interest earned at the rate of \(r \% /\) year compounded \(m\) times a year. $$ S=20,000, r=4, t=6, m=2 $$
4 step solution
Problem 9
A bank deposit paying simple interest grew from an initial sum of $$\$ 1000$$ to a sum of $$\$ 1075$$ in 9 mo. Find the interest rate.
4 step solution
Problem 10
Find the periodic payment \(R\) required to accumulate a sum of \(S\) dollars over \(t\) yr with interest earned at the rate of \(r \% /\) year compounded \(m\) times a year. $$ S=40,000, r=4, t=9, m=4 $$
4 step solution
Problem 10
Find the present value of each ordinary annuity. $$\$ 1200 /$$ semiannual period for 6 yr at \(10 \%\) lyear compounded semiannually
3 step solution
Problem 10
Determine the simple interest rate at which $$\$ 1200$$ will grow to $$\$ 1250$$ in 8 mo.
3 step solution
Problem 11
Find the periodic payment \(R\) required to accumulate a sum of \(S\) dollars over \(t\) yr with interest earned at the rate of \(r \% /\) year compounded \(m\) times a year. $$ S=100,000, r=4.5, t=20, m=6 $$
5 step solution
Problem 12
Find the periodic payment \(R\) required to accumulate a sum of \(S\) dollars over \(t\) yr with interest earned at the rate of \(r \% /\) year compounded \(m\) times a year. $$ S=120,000, r=4.5, t=30, m=6 $$
4 step solution
Problem 12
Find the present value of each ordinary annuity. $$\$ 3000 /$$ semiannual period for 6 yr at \(11 \%\) year compounded semiannually
3 step solution
Problem 12
Find the accumulated amount \(A\) if the principal \(P\) is invested at the interest rate of \(r /\) year for \(t\) yr. $$ P=\$ 1000, r=8 \frac{1}{2} \%, t=6, \text { compounded annually } $$
4 step solution
Problem 13
Find the periodic payment \(R\) required to accumulate a sum of \(S\) dollars over \(t\) yr with interest earned at the rate of \(r \% /\) year compounded \(m\) times a year. $$ S=250,000, r=10.5, t=25, m=12 $$
7 step solution
Problem 13
Find the accumulated amount \(A\) if the principal \(P\) is invested at the interest rate of \(r /\) year for \(t\) yr. $$ P=\$ 2500, r=7 \%, t=10, \text { compounded semiannually } $$
5 step solution
Problem 14
Find the periodic payment \(R\) required to accumulate a sum of \(S\) dollars over \(t\) yr with interest earned at the rate of \(r \% /\) year compounded \(m\) times a year. $$ S=350,000, r=7.5, t=10, m=12 $$
4 step solution
Problem 14
Find the accumulated amount \(A\) if the principal \(P\) is invested at the interest rate of \(r /\) year for \(t\) yr. $$ P=\$ 2500, r=9 \%, t=10 \frac{1}{2}, \text { compounded semiannually } $$
5 step solution
Problem 15
Suppose payments were made at the end of each quarter into an ordinary annuity earning interest at the rate of \(10 \% /\) year compounded quarterly. If the future value of the annuity after \(5 \mathrm{yr}\) is \(\$ 50,000\), what was the size of each payment?
4 step solution
Problem 15
If a merchant deposits $$\$ 1500$$ at the end of each tax year in an IRA paying interest at the rate of \(8 \% /\) year compounded annually, how much will she have in her account at the end of 25 yr?
5 step solution
Problem 15
Find the accumulated amount \(A\) if the principal \(P\) is invested at the interest rate of \(r /\) year for \(t\) yr. $$ P=\$ 12,000, r=8 \%, t=10 \frac{1}{2}, \text { compounded quarterly } $$
5 step solution
Problem 16
If Jackson deposits $$\$ 100$$ at the end of each month in a savings account earning interest at the rate of \(8 \%\) /year compounded monthly, how much will he have on deposit in his savings account at the end of \(6 \mathrm{yr}\), assuming that he makes no withdrawals during that period?
5 step solution
Problem 16
Find the accumulated amount \(A\) if the principal \(P\) is invested at the interest rate of \(r /\) year for \(t\) yr. $$ P=\$ 42,000, r=7 \frac{3}{4} \%, t=8, \text { compounded quarterly } $$
3 step solution
Problem 17
Suppose payments will be made for \(6 \frac{1}{2}\) yr at the end of each semiannual period into an ordinary annuity earning interest at the rate of \(7.5 \% /\) year compounded semiannually. If the present value of the annuity is $$\$ 35,000$$, what should be the size of each payment?
3 step solution
Problem 17
Linda has joined a "Christmas Fund Club" at her bank. At the end of every month, December through October inclusive, she will make a deposit of $$\$ 40$$ in her fund. If the money earns interest at the rate of \(7 \% /\) year compounded monthly, how much will she have in her account on December 1 of the following year?
6 step solution
Problem 17
Find the accumulated amount \(A\) if the principal \(P\) is invested at the interest rate of \(r /\) year for \(t\) yr. $$ P=\$ 150,000, r=14 \%, t=4, \text { compounded monthly } $$
3 step solution
Problem 18
Suppose payments will be made for \(9 \frac{1}{4}\) yr at the end of each month into an ordinary annuity earning interest at the rate of \(6.25 \% /\) year compounded monthly. If the present value of the annuity is $$\$ 42,000$$, what should be the size of each payment?
5 step solution
Problem 18
Robin, who is self-employed, contributes $$\$5000$$/year into a Keogh account. How much will he have in the account after \(25 \mathrm{yr}\) if the account earns interest at the rate of \(8.5 \% /\) year compounded yearly?
3 step solution
Problem 19
A sum of $$\$ 100,000$$ is to be repaid over a 10 -yr period through equal installments made at the end of each year. If an interest rate of \(10 \% /\) year is charged on the unpaid balance and interest calculations are made at the end of each year, determine the size of each installment so that the loan (principal plus interest charges) is amortized at the end of \(10 \mathrm{yr}\).
5 step solution
Problem 19
As a fringe benefit for the past 12 yr, Colin's employer has contributed $$\$ 100$$ at the end of each month into an employee retirement account for Colin that pays interest at the rate of \(7 \% /\) year compounded monthly. Colin has also contributed $$\$ 2000$$ at the end of each of the last 8 yr into an IRA that pays interest at the rate of \(9 \% /\) year compounded yearly. How much does Colin have in his retirement fund at this time?
5 step solution
Problem 19
Find the accumulated amount \(A\) if the principal \(P\) is invested at the interest rate of \(r /\) year for \(t\) yr. $$ P=\$ 150,000, r=12 \%, t=3, \text { compounded daily } $$
4 step solution
Problem 20
What monthly payment is required to amortize a loan of $$\$ 30,000$$ over \(10 \mathrm{yr}\) if interest at the rate of \(12 \% /\) year is charged on the unpaid balance and interest calculations are made at the end of each month?
4 step solution
Problem 20
The Pirerras are planning to go to Europe 3 yr from now and have agreed to set aside $$\$ 150 /$$ month for their trip. If they deposit this money at the end of each month into a savings account paying interest at the rate of \(8 \% /\) year compounded monthly, how much money will be in their travel fund at the end of the third year?
4 step solution