/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 79 Investment \(A\) sum of \(\$ 500... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Investment \(A\) sum of \(\$ 5000\) is invested in three mutual funds that pay \(8 \%, 11 \%,\) and \(14 \%\) annual interest rates. The amount of money invested in the fund paying \(14 \%\) equals the total amount of money invested in the other two funds, and the total annual interest from all three funds is \(\$ 595\) (a) Write a system of equations whose solution gives the amount invested in each mutual fund. Be sure to state what cach variable represents. (b) Solve the system of equations.

Short Answer

Expert verified
Invest $1000 at 8%, $1500 at 11%, and $2500 at 14%.

Step by step solution

01

Define Variables

Let \( x \) be the amount invested at 8%, \( y \) be the amount invested at 11%, and \( z \) be the amount invested at 14%.
02

Write Equations Based on Total Investment and Interest

The total amount invested is \(5000, so the first equation is:\[x + y + z = 5000\]The total annual interest from all three funds is \)595, so the second equation is:\[0.08x + 0.11y + 0.14z = 595\]
03

Write Equation Based on Investment Condition

The amount invested in the 14% fund equals the amount invested in the other two funds combined, creating the third equation:\[z = x + y\]
04

Solve the System of Equations

Substitute \(z = x + y \) from the third equation into the first two equations:1. \(x + y + (x + y) = 5000\) simplifies to:\[\2x + 2y = 5000 \ x + y = 2500\]2. \(0.08x + 0.11y + 0.14(x + y) = 595\) simplifies to:\[\0.08x + 0.11y + 0.14x + 0.14y = 595 \ 0.22x + 0.25y = 595\]Now we have two equations:\[\x + y = 2500 \0.22x + 0.25y = 595\]Solve the first equation for \(x\):\[x = 2500 - y\]Substitute \(x = 2500 - y\) into the second equation:\[\0.22(2500 - y) + 0.25y = 595 \550 - 0.22y + 0.25y = 595 \0.03y = 45 \y = 1500\]Substitute \(y = 1500\) back into \(x = 2500 - y\):\[\x = 2500 - 1500 = 1000\]Substitute \(x = 1000\) and \(y = 1500\) into \(z = x + y\):\[\z = 1000 + 1500 = 2500\]
05

Verify the Solution

Check the solution to ensure it satisfies all original equations:1. \(x + y + z = 1000 + 1500 + 2500 = 5000\) is correct.2. \(0.08(1000) + 0.11(1500) + 0.14(2500) = 80 + 165 + 350 = 595\) is correct.3. \(z = x + y\) verifies as \(2500 = 1000 + 1500\). All equations are satisfied.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Investment Problems
Investment problems often involve determining the allocation of funds across different assets to meet specific objectives, such as maximizing returns or meeting interest payment goals. In the given exercise, an amount of $5000 is distributed among three mutual funds, each offering different interest rates. The complexity arises from conditions such as keeping the sum allocated in one higher interest fund equal to the combined amount invested in others.

To solve such problems efficiently, forming a system of equations is essential:
  • Define variables to represent investments in each fund.
  • Translate the problem's conditions into mathematical equations.
  • Ensure the equations reflect both the total investment amount and the constraints on individual allocations.
By solving these equations, the amount allocated in each fund can be determined. It's crucial to comprehend how these equations interrelate, giving insights into managing investments wisely.
Mutual Funds
Mutual funds are investment vehicles that pool money from multiple investors to invest in a diversified portfolio of assets like stocks and bonds. Each investor owns shares that represent a part of these holdings. The variety in mutual funds allows investors to optimize their portfolios based on risk tolerance and expected returns.

In solving the original exercise, understanding mutual funds helps appreciate the impact of distributing investments across funds with varying interest rates:
  • An 8% fund is relatively low-risk with moderate returns.
  • An 11% fund offers balanced risk and reward.
  • A 14% fund is likely higher risk, promising higher returns.
Investors must assess their strategies to align with financial goals, using the diversity of mutual funds to mitigate risks while still aiming for fruitful returns. This exercise highlights how effectively managing mutual fund investments can generate desired income levels.
Interest Rates
Interest rates are the percentage return on investments over a given period and are pivotal in investment decision-making. They directly influence how much earnings one might expect from a mutual fund. In our exercise, different interest rates alter the total interest gained from the investment and illustrate choosing among potential returns:
  • A lower interest rate, like 8%, means safer, but less lucrative investments.
  • Mid-range rates, e.g., 11%, typically offer balanced options.
  • High rates, like 14%, come with increased risk but also lucrative returns.
Understanding interest rates is key to formulating the system of equations in the exercise. Here, annual interests play a role in how funds are distributed among the available options, paving the way to achieve the total expected annual return ($595 in this case). With this understanding, investors can properly strategize fund distribution to maximize returns while considering their risk appetite.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Translations (Refer to the discussion in this section about translating a point.) Find a \(3 \times 3\) matrix A that performs the following translation of a point \((x, y)\) represented by \(X .\) Find \(A^{-1}\) and describe what it computes. Leontief Economic Model Suppose that a closed eco nomic region has three industries: service, electrical power and tourism. The service industry uses \(20 \%\) of its own production, \(40 \%\) of the electrical power, and \(80 \%\) of the tourism. The power company use \(40 \%\) of the service indus try, \(20 \%\) of the electrical power, and \(10 \%\) of the tourism The tourism industry uses \(40 \%\) of the service industry \(10 \%\) of the tourism. (A) Let \(S, E,\) and \(T\) be the numbers of units produced by the service, electrical, and tourism industries, respectively. The following system of linear equations can be used to determine the relative number of units each industry needs to produce. (This model assumes that all production is consumed by the region.) $$ \begin{aligned} &0.25+0.4 E+0.8 T=S\\\ &\begin{array}{l} 0.45+0.2 E+0.1 T=E \\ 0.45+0.4 E+0.1 T=T \end{array} \end{aligned} $$ Solve the system and write the solution in terms of \(T\). (B) If tourism produces 60 units, how many units should the service and electrical industries produce?

If possible, find \(A B\) and \(B A\). $$A=\left[\begin{array}{rr}-3 & 1 \\\2 & -4\end{array}\right], \quad B=\left[\begin{array}{rrr}1 & 0 & -2 \\\\-4 & 8 & 1\end{array}\right]$$

The variable \(z\) varies jointly as the third powers of \(x\) and y. If \(z=2160\) when \(x=3\) and \(y=4,\) find \(z\) when \(x=2\) and \(y=5\).

If possible, find \(A B\) and \(B A\). $$A=\left[\begin{array}{rrrr}1 & -1 & 3 & -2 \\\1 & 0 & 3 & 4 \\\2 & -2 & 0 & 8 \end{array}\right], \quad B=\left[\begin{array}{rr}1 & -1 \\\0 & 5 \\\2 & 3 \\\\-5 & 4\end{array}\right]$$

Minimizing Cost Two substances, \(\mathbf{X}\) and \(\mathbf{Y}\), are found in pet food. Each substance contains the ingrodients A and B. Substance \(X\) is \(20 \%\) ingredient \(A\) and \(50 \%\) ingredient B. Substance \(Y\) is \(50 \%\) ingredient \(A\) and \(30 \%\) ingredient \(\mathbf{B}\). The cost of substance \(\mathbf{X}\) is \(\$ 2\) per pound, and the cost of substance \(Y\) is \(\$ 3\) per pound. The pet store needs at least 251 pounds of ingredient \(A\) and at least 200 pounds of ingredient \(B\). If cost is to be minimal, how many pounds of each substance should be ordered? Find the minimum cost.

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.