Solve for Unit Price: $8 Difference Between Apples and Cucumbers

System of Equations with Price Differences

A man buys 3 kg of apples and 5 kg of cucumbers for $48.

The price of 1 kg of apples is $8 more expensive than the price of 1 kg of cucumbers.

What is the price of 1 kg of cucumbers?

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

A man buys 3 kg of apples and 5 kg of cucumbers for $48.

The price of 1 kg of apples is $8 more expensive than the price of 1 kg of cucumbers.

What is the price of 1 kg of cucumbers?

2

Step-by-step solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the prices of apples and cucumbers in terms of a variable.
  • Step 2: Set up the equation for the total cost.
  • Step 3: Solve the equation to find the price of cucumbers.

Now, let's work through each step:

Step 1: Let the price per kg of cucumbers be c c dollars. Thus, the price per kg of apples is c+8 c + 8 dollars.

Step 2: Express the total cost of the items:

For 3 kg of apples: 3×(c+8) 3 \times (c + 8)
For 5 kg of cucumbers: 5×c 5 \times c

These add up to give the total cost:

3(c+8)+5c=48 3(c + 8) + 5c = 48

Step 3: Solve the equation.

Expand the equation:

3c+24+5c=48 3c + 24 + 5c = 48

Combine like terms:

8c+24=48 8c + 24 = 48

Subtract 24 from both sides:

8c=24 8c = 24

Divide by 8:

c=3 c = 3

Therefore, the price of 1 kg of cucumbers is 3 3 dollars.

3

Final Answer

3 3

Key Points to Remember

Essential concepts to master this topic
  • Variable Setup: Let cheaper item be x, expensive item be x + difference
  • Technique: Use 3(c + 8) + 5c = 48 to combine quantities and costs
  • Check: Verify: 3(11) + 5(3) = 33 + 15 = 48 ✓

Common Mistakes

Avoid these frequent errors
  • Setting up variables incorrectly for the price relationship
    Don't make apples = x and cucumbers = x - 8 when apples cost MORE! This gives negative cucumber prices. Always let the cheaper item be your variable, so if apples cost $8 more, then cucumbers = c and apples = c + 8.

Practice Quiz

Test your knowledge with interactive questions

\( 11=a-16 \)

\( a=\text{?} \)

FAQ

Everything you need to know about this question

Why should I let the cheaper item be my variable?

+

Making the cheaper item your variable prevents negative prices! Since apples cost $8 more than cucumbers, if cucumbers = c, then apples = c + 8 (always positive).

How do I know which item costs more from the problem?

+

Look for key phrases like '$8 more expensive than' or 'costs $8 more'. The item mentioned first is usually the more expensive one in these contexts.

What if I get a decimal or fraction answer?

+

That's totally normal for price problems! Always check that your answer makes practical sense - prices should be positive and reasonable for the items described.

Can I solve this using substitution instead of one variable?

+

Yes! You could use two variables: a = apple price, c = cucumber price. Then you'd have the system: 3a + 5c = 48 and a = c + 8. Both methods work!

How do I check my answer makes sense?

+
  • Math check: Substitute back into original equation
  • Logic check: Apples should cost $8 more than cucumbers
  • Reality check: Do the prices seem reasonable?

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Linear Equations (One Variable) questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime

More Questions

Click on any question to see the complete solution with step-by-step explanations