<< Chapter < Page Chapter >> Page >

Notice that in this example, Loren’s brother paid Loren interest, just like a bank would have paid interest if Loren invested his money there.

Jim loaned his sister $5,000 to help her buy a house. In 3 years, she paid him the $5,000, plus $900 interest. What was the rate of interest?

6%

Got questions? Get instant answers now!

Hang borrowed $7,500 from her parents to pay her tuition. In 5 years, she paid them $1,500 interest in addition to the $7,500 she borrowed. What was the rate of interest?

4%

Got questions? Get instant answers now!

Eduardo noticed that his new car loan papers stated that with a 7.5% interest rate, he would pay $6,596.25 in interest over 5 years. How much did he borrow to pay for his car?

Solution

Step 1. Read the problem. Step 2. Identify what we are looking for. the amount borrowed (the principal) Step 3. Name what we are looking for. Choose a variable to represent that quantity . Let P = principal borrowed. Step 4. Translate into an equation. Write the formula. Substitute in the given information. Step 5. Solve the equation. Divide. I = P r t 6,596.25 = P ( 0.075 ) ( 5 ) 6,596.25 = 0.375 P 17,590 = P Step 6. Check : Does this make sense? I = P r t 6,596.25 = ? ( 17,590 ) ( 0.075 ) ( 5 ) 6,596.25 = 6,596.25 Step 7. Answer the question with a complete sentence. The principal was $17,590.

Got questions? Get instant answers now!
Got questions? Get instant answers now!

Sean’s new car loan statement said he would pay $4,866.25 in interest from an interest rate of 8.5% over 5 years. How much did he borrow to buy his new car?

$11,450

Got questions? Get instant answers now!

In 5 years, Gloria’s bank account earned $2,400 interest at 5%. How much had she deposited in the account?

$9,600

Got questions? Get instant answers now!

Solve applications with discount or mark-up

Applications of discount are very common in retail settings. When you buy an item on sale, the original price has been discounted by some dollar amount. The discount rate    , usually given as a percent, is used to determine the amount of the discount. To determine the amount of discount    , we multiply the discount rate by the original price.

We summarize the discount model in the box below.

Discount

amount of discount = discount rate × original price sale price = original price amount of discount

Keep in mind that the sale price should always be less than the original price.

Elise bought a dress that was discounted 35% off of the original price of $140. What was the amount of discount and the sale price of the dress?

Solution


Original price = $ 140 Discount rate = 35 % Discount = ?
Step 1. Read the problem. Step 2. Identify what we are looking for. the amount of discount Step 3. Name what we are looking for. Choose a variable to represent that quantity . Let d = the amount of discount. Step 4. Translate into an equation. Write a sentence that gives the information to find it. The discount is 35% of $140. Translate into an equation. d = 0.35 ( 140 ) Step 5. Solve the equation. d = 49 Step 6. Check : Does this make sense? Is a $49 discount reasonable for a $140 dress? Yes. Step 7. Write a complete sentence to answer the question. The amount of discount was $49.


Read the problem again.

Step 1. Identify what we are looking for. the sale price of the dress
Step 2. Name what we are looking for.
Choose a variable to represent that quantity. Let s = the sale price.
Step 3. Translate into an equation.
Write a sentence that gives the information to find it. .
Translate into an equation. .
Step 4. Solve the equation. .
Step 5. Check. Does this make sense?
Is the sale price less than the original price?
Yes, $91 is less than $140.
Step 6. Answer the question with a complete sentence. The sale price of the dress was $91.

Got questions? Get instant answers now!
Got questions? Get instant answers now!

Questions & Answers

the diagram of the digestive system
Assiatu Reply
How does twins formed
William Reply
They formed in two ways first when one sperm and one egg are splited by mitosis or two sperm and two eggs join together
Oluwatobi
what is genetics
Josephine Reply
Genetics is the study of heredity
Misack
how does twins formed?
Misack
What is manual
Hassan Reply
discuss biological phenomenon and provide pieces of evidence to show that it was responsible for the formation of eukaryotic organelles
Joseph Reply
what is biology
Yousuf Reply
the study of living organisms and their interactions with one another and their environments
AI-Robot
the study of living organisms and their interactions with one another and their environment.
Wine
discuss the biological phenomenon and provide pieces of evidence to show that it was responsible for the formation of eukaryotic organelles in an essay form
Joseph Reply
what is the blood cells
Shaker Reply
list any five characteristics of the blood cells
Shaker
lack electricity and its more savely than electronic microscope because its naturally by using of light
Abdullahi Reply
advantage of electronic microscope is easily and clearly while disadvantage is dangerous because its electronic. advantage of light microscope is savely and naturally by sun while disadvantage is not easily,means its not sharp and not clear
Abdullahi
cell theory state that every organisms composed of one or more cell,cell is the basic unit of life
Abdullahi
is like gone fail us
DENG
cells is the basic structure and functions of all living things
Ramadan
What is classification
ISCONT Reply
is organisms that are similar into groups called tara
Yamosa
in what situation (s) would be the use of a scanning electron microscope be ideal and why?
Kenna Reply
A scanning electron microscope (SEM) is ideal for situations requiring high-resolution imaging of surfaces. It is commonly used in materials science, biology, and geology to examine the topography and composition of samples at a nanoscale level. SEM is particularly useful for studying fine details,
Hilary
cell is the building block of life.
Condoleezza Reply
what is cell divisoin?
Aron Reply
Diversity of living thing
ISCONT
what is cell division
Aron Reply
Cell division is the process by which a single cell divides into two or more daughter cells. It is a fundamental process in all living organisms and is essential for growth, development, and reproduction. Cell division can occur through either mitosis or meiosis.
AI-Robot
What is life?
Allison Reply
life is defined as any system capable of performing functions such as eating, metabolizing,excreting,breathing,moving,Growing,reproducing,and responding to external stimuli.
Mohamed
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply
Practice Key Terms 9

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, Elementary algebra. OpenStax CNX. Jan 18, 2017 Download for free at http://cnx.org/content/col12116/1.2
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Elementary algebra' conversation and receive update notifications?

Ask