High school simple algebra word problem

In summary, a high school simple algebra word problem is a question that requires the use of basic algebra concepts to solve. To approach solving these problems, one should carefully read the problem, identify given information, and set up equations to solve for the unknown variable. Common expressions and equations used in these problems include linear and quadratic equations, inequalities, and systems of equations. To check answers, one can plug it back into the original problem or use a calculator. Tips for improving skills in solving these problems include practice, reviewing basic concepts and equations, and seeking help from a teacher or tutor.
  • #1
randyrandy
12
1
The 100W light bulb (cost 0.60 dollars) is not going to be used anymore and is being replaced with the 20W (cost 3 dollars) low energy light bulb.
If electricity is charged at $0.15 per kWh, for how many hours must the low energy bulb be used in order for the lower cost of running it to exactly compensate for its higher initial cost?

A. 0.25
B 250.00
C 200.00
D 160.00
E 720.00

answer: D 160.00

why?

On first appearance you would think:
0.60 + 0.1 * 0.15 * t = 3.00 + 0.02 * 0.15 * t
t = 200

But that's the wrong answer. That's one of the trap choices.

How do you get to 160?

What am I misunderstanding or missing?
 
Last edited:
Mathematics news on Phys.org
  • #2
I agree with your solution ... 200 hrs.
 
  • #3
help please said:
The 100W light bulb (cost 0.60 dollars) is not going to be used anymore and is being replaced with the 20W (cost 3 dollars) low energy light bulb.
If electricity is charged at $0.15 per kWh, for how many hours must the low energy bulb be used in order for the lower cost of running it to exactly compensate for its higher initial cost?

A. 0.25
B 250.00
C 200.00
D 160.00
E 720.00

answer: D 160.00

why?

On first appearance you would think:
0.60 + 0.1 * 0.15 * t = 3.00 + 0.02 * 0.15 * t
t = 200

But that's the wrong answer. That's one of the trap choices.

How do you get to 160?

What am I misunderstanding or missing?
If you already have a 100W light bulb that is not going to be used anymore, then you don't need to spend $0.60 on a new one. So I would leave out the term 0.60 in the equation, which then becomes
0.1 * 0.15 * t = 3.00 + 0.02 * 0.15 * t.

But that leads to the answer t = 250. I don't see any way to get the answer 160 unless there is some further information that has been omitted from the question.
 

1. What is a simple algebra word problem?

A simple algebra word problem is a mathematical problem that uses letters or symbols to represent unknown quantities, and requires the use of basic algebraic operations (such as addition, subtraction, multiplication, and division) to solve.

2. How do I solve a high school simple algebra word problem?

To solve a high school simple algebra word problem, you can follow these steps:

  1. Read the problem carefully to understand what is being asked.
  2. Identify the unknown quantity and assign it a variable (usually represented by a letter).
  3. Write down any given information in terms of the variable.
  4. Use the given information and the basic algebraic operations to set up an equation.
  5. Solve the equation to find the value of the variable.
  6. Check your solution by plugging it back into the original problem.

3. What are some common types of high school simple algebra word problems?

Some common types of high school simple algebra word problems include problems involving age, distance, money, and mixtures. These problems can also involve multiple unknown quantities and may require the use of systems of equations to solve.

4. What are some tips for solving high school simple algebra word problems?

Here are some tips for solving high school simple algebra word problems:

  • Read the problem carefully and make sure you understand what is being asked.
  • Identify the unknown quantity and assign it a variable.
  • Draw a diagram or make a table if it helps you visualize the problem.
  • Use keywords (such as "more than," "less than," "total," etc.) to help you set up the equation.
  • Check your solution by plugging it back into the original problem.

5. Where can I find more practice problems for high school simple algebra word problems?

You can find more practice problems for high school simple algebra word problems in your textbook, online resources, or by asking your teacher for additional practice materials. You can also create your own word problems using real-life situations to practice solving them.

Similar threads

Programs How good is this applied math program?
    • STEM Academic Advising
Replies
13
Views
2K
Algebra Help for Word Problems: Profit and Cost Analysis Explained
    • Introductory Physics Homework Help
Replies
2
Views
2K
Mathematica This Week's Finds in Mathematical Physics (Week 267)
    • MATLAB, Maple, Mathematica, LaTeX
Replies
1
Views
2K

Hot Threads

Recent Insights

Back
Top