Solve Mixed Number Division: 7½ ÷ 2½ Step-by-Step

Mixed Number Division with Improper Fractions

712:212= 7\frac{1}{2}:2\frac{1}{2}=

❤️ Continue Your Math Journey!

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

Step-by-step video solution

Watch the teacher solve the problem with clear explanations
00:00 Solve
00:03 Convert mixed fractions to fractions
00:19 Calculate the numerators
00:32 Write division as a fraction
00:39 Multiply by the reciprocal
00:48 Calculate the multiplications
00:59 Calculate the quotient
01:02 And this is the solution to the problem

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

712:212= 7\frac{1}{2}:2\frac{1}{2}=

2

Step-by-step solution

To solve the problem of dividing the mixed numbers 712 7\frac{1}{2} by 212 2\frac{1}{2} , follow these steps:

  • Step 1: Convert the mixed numbers to improper fractions.
  • Step 2: Divide the fractions by multiplying by the reciprocal.
  • Step 3: Simplify the resulting fraction to find the answer.

Now, let’s break it down step-by-step:

Step 1: Convert 712 7\frac{1}{2} to an improper fraction. To do this, multiply the whole number 7 by the denominator 2 and add the numerator 1:
7×2+1=14+1=15 7 \times 2 + 1 = 14 + 1 = 15 .

This makes the improper fraction 152\frac{15}{2}.

Convert 212 2\frac{1}{2} in a similar manner:
2×2+1=4+1=5 2 \times 2 + 1 = 4 + 1 = 5 , giving 52\frac{5}{2}.

Step 2: Divide 152\frac{15}{2} by 52\frac{5}{2} by multiplying 152\frac{15}{2} by the reciprocal of 52\frac{5}{2}, which is 25\frac{2}{5}:
152×25=15×22×5=3010\frac{15}{2} \times \frac{2}{5} = \frac{15 \times 2}{2 \times 5} = \frac{30}{10}.

Step 3: Simplify 3010\frac{30}{10}: divide the numerator and the denominator by their greatest common divisor, 10,
3010=30÷1010÷10=31=3\frac{30}{10} = \frac{30 \div 10}{10 \div 10} = \frac{3}{1} = 3.

Therefore, the solution to 712÷212 7\frac{1}{2} \div 2\frac{1}{2} is 3 3 , which corresponds to choice 3.

3

Final Answer

3 3

Key Points to Remember

Essential concepts to master this topic
  • Rule: Convert mixed numbers to improper fractions before dividing
  • Technique: Multiply by reciprocal: 152×25=3010 \frac{15}{2} \times \frac{2}{5} = \frac{30}{10}
  • Check: Verify 3×212=712 3 \times 2\frac{1}{2} = 7\frac{1}{2} using multiplication ✓

Common Mistakes

Avoid these frequent errors
  • Dividing whole numbers and fractions separately
    Don't divide 7 ÷ 2 = 3.5 and 12÷12=1 \frac{1}{2} ÷ \frac{1}{2} = 1 separately = wrong answer 4.5! This ignores the proper structure of mixed numbers. Always convert to improper fractions first, then divide as single fractions.

Practice Quiz

Test your knowledge with interactive questions

\( 2\frac{5}{6}\times1\frac{1}{4}= \)

FAQ

Everything you need to know about this question

Why can't I just divide the whole numbers and fractions separately?

+

Mixed numbers are single values, not separate parts! 712 7\frac{1}{2} means 7.5, not "7 plus 12 \frac{1}{2} ". Dividing parts separately gives completely wrong answers.

How do I convert a mixed number to an improper fraction?

+

Multiply the whole number by the denominator, then add the numerator. For 712 7\frac{1}{2} : (7 × 2) + 1 = 15, so it becomes 152 \frac{15}{2} .

What's the reciprocal and why do I multiply by it?

+

The reciprocal flips the fraction: reciprocal of 52 \frac{5}{2} is 25 \frac{2}{5} . Division by a fraction equals multiplication by its reciprocal - this is a fundamental rule!

Do I always get a whole number when dividing mixed numbers?

+

No! You might get another mixed number, improper fraction, or whole number. In this case, 3010 \frac{30}{10} simplified perfectly to 3, but that won't always happen.

How can I check my answer is correct?

+

Use multiplication to verify: 3×212 3 \times 2\frac{1}{2} should equal 712 7\frac{1}{2} . Convert: 3×52=152=712 3 \times \frac{5}{2} = \frac{15}{2} = 7\frac{1}{2}

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Mixed Fractions 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