1.3.2: Exercise N.3
- Page ID
- 147898
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)(1) It was estimated that, in the United States, the total student loan debt surpassed total credit card debt and auto loans for the first time in 2011, with total student loan debt reaching the $1 trillion mark.
(a) Write this total loan amount in standard form (written out with all the zeros).
(b) If the average interest rate on these loans is 6%, estimate how much interest is being paid on the $1 trillion dollars of student loan debt each year. Write your answer in standard form.
(2) By federal law, the interest rate on subsidized Stafford loans changes each year, based on certain financial market rates. The interest used on a Stafford loan is determined by the first disbursement date of the loan. For Stafford loans taken out for the 2022-2023 school year, the interest rate is 4.99%.3 Think about the situation of Sandra and her student loan ($20,000) from the collaboration.
(a) At the 4.99% rate, will Sandra pay less, pay more, or pay the same each month than she would with an interest rate of 6.8%?
(b) Estimate again how much her monthly payments would be if she is charged an interest rate of 4.99% and she takes the full 10 years to repay the loan. Note: It is assumed that you will use the “average balance method” which was discussed during the collaboration. Round to the nearest dollar.
(3) (a) You want to purchase a new car. You are offered a loan for $16,000 with an annual interest rate of 6% and a 36-month repayment period. Estimate how much your monthly payment would be for this loan. Use the “average balance method” to estimate the total amount you will pay over the 36 months for this $16,000 car loan. Round to the nearest dollar.
(b) Calculate an estimate how much your monthly payment would be for this loan. Round your answer to the nearest dollar.
(4) Suppose you decide before buying the car that you can’t afford the monthly payment you calculated in Question 3(b), so you take out the same $16,000 loan with an interest rate of 6%, but now with a 60-month repayment period.
(a) Calculate an estimate of the total amount you would pay over the 60 months for the car loan in this case.
(b) Calculate an estimate for your monthly payment with the 60-month option.
(c) Calculate an estimate how much more you will pay for the car if you choose the 60-month loan instead of the 36-month loan.
(5) It is estimated that the average principal owed for student loans in 2021 was $37,338 per student.4 If market rates go up and the interest rate for student loans increases from 4.99% to 6.8%, estimate how much more interest students will pay over a 10-year repayment period for this average amount owed, at the 6.8% rate as compared with a rate of 4.99%. Round all figures to the nearest dollar.
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3 https://www.edvisors.com/student-loans/federal-student-loans/interest-rates/


