Lesson 6.1Division Expressions with Fractions and Whole Numbers
Set B · Version ASecond form · supported practice
Learning target I can explain what dividing with a whole number and a unit fraction means — how many groups fit, or how much is in one group — find the quotient with a model, and check it by multiplying.
Why This Matters Agent Reyes finds a 3-foot strip of tape at the crime scene. The lab needs the tape cut into 1/4-foot sections for analysis. How many sections can be made? The answer cracks the code to the locked evidence vault.
RememberDivision Expressions with Fractions and Whole Numbers
Dividing Whole Numbers & Fractions Dividing by a fraction asks one question: how many of that small piece fit inside the whole amount? For 3 ÷ 1/4, we ask how many 1/4-foot pieces fit into 3 feet.
- Name the question: 3 ÷ 1/4 asks how many 1/4s fit in 3, and 1/2 ÷ 4 asks how much is in each of 4 equal shares.
- Use the model: each whole holds 4 fourths, so 3 wholes hold 3 × 4 = 12 fourths, and 3 ÷ 1/4 =
- Check by multiplying: 12 × 1/4 =
- Shortcut: dividing by 1/4 gives the same answer as multiplying by its reciprocal, 4
Words: Reciprocal (Recíproco)Quotient (Cociente)Dividend (Dividendo)Divisor (Divisor)Unit fraction (Fracción unitaria)
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1Write the name of the correct group on each line.
Sort each statement: does dividing by the fraction give a result GREATER than the dividend, or LESS than the dividend?
- 5 ÷ 1/3
- 8 ÷ 1/2
- 6 ÷ 1/4
- 4 ÷ 2
- 10 ÷ 5
- 12 ÷ 3
Hint Work out each quotient first, then compare it with the dividend — the number being divided.
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2Circle the letter of the best answer. Show how you know.
What is 6 ÷ 1/5?
- A1
- B5/6
- C6/5
- D30
Hint 6 ÷ 1/5 asks: how many 1/5-size pieces fit into 6 wholes? Predict first — more or fewer than 6?
Show your work -
3Circle the letter of the best answer. Show how you know.
What is 4.8 ÷ 2?
- A0.24
- B2.4
- C2.6
- D24
Show your work
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4Circle the letter of the best answer. Show how you know.
Agent Reyes has used 6 feet of evidence tape, and that is 1/2 of a full roll. How many feet of tape are on a full roll? (6 ÷ 1/2 asks how much is in ONE whole roll.)
- A3 feet
- B12 feet
- C6 1/2 feet
- D1/12 foot
Hint The 6 feet is only part of the roll. Which part?
Show your work
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5Find the mistake. Explain it, then show the correct work.
Spot the Common Mistake
- 1ProblemHow many 1/3-foot pieces fit into 4 feet of tape? Find 4 ÷ 1/3.
- 2Student writesDividing makes the answer smaller, so 4 ÷ 1/3 = 4 ÷ 3 ≈ 1.3 pieces.
- 3Student's answerAbout 1.3 pieces
Which step has the mistake? Explain what went wrong, then show the correct work.
Hint How many 1/3-foot pieces fit inside just ONE foot?
Correct workCorrect answer: -
6Find the mistake. Explain it, then show the correct work.
Spot the Common Mistake
- 1ProblemHow many 1/5-cup scoops fill a 6-cup container? Find 6 ÷ 1/5.
- 2Student writesI will flip the first number instead of the divisor: 6 ÷ 1/5 = 1/6 × 5 = 5/6 scoop.
- 3Student's answer5/6 of a scoop
Which step has the mistake? Explain what went wrong, then show the correct work.
Hint Which number do you flip when you divide — the dividend (6) or the divisor (1/5)?
Correct workCorrect answer:
Explain your thinkingWhy does dividing by a unit fraction always give a number larger than the dividend?
Sentence starter Dividing by 1/3 means finding how many ___ fit into ___, so the quotient is ___ than the dividend.
Lesson 6.1Division Expressions with Fractions and Whole Numbers
Set B · Version BSecond form · core practice
Learning target I can explain what dividing with a whole number and a unit fraction means — how many groups fit, or how much is in one group — find the quotient with a model, and check it by multiplying.
Why This Matters Agent Reyes finds a 3-foot strip of tape at the crime scene. The lab needs the tape cut into 1/4-foot sections for analysis. How many sections can be made? The answer cracks the code to the locked evidence vault.
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1Circle the letter of the best answer. Show how you know.
What is 8.4 ÷ 0.7?
- A0.12
- B1.2
- C12
- D120
Show your work -
2Circle the letter of the best answer. Show how you know.
What is 14.4 ÷ 1.2?
- A0.12
- B1.2
- C12
- D120
Show your work -
3Circle the letter of the best answer. Show how you know.
What is 3.78 ÷ 0.6?
- A0.063
- B0.63
- C6.3
- D63
Show your work
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4Circle the letter of the best answer. Show how you know.
A detective has 6 yards of crime scene tape. She needs to mark off sections that are each 1/3 of a yard. She wants to know how many sections she can mark. 6 ÷ 1/3 = ?
- A2
- B3
- C6
- D18
Show your work -
5Circle the letter of the best answer. Show how you know.
A detective has 6 yards of crime scene tape. She needs to mark off sections that are each 1/3 of a yard. She wants to know how many sections she can mark. Why is the answer bigger than 6?
- ABecause the pieces are smaller than a whole yard, so many of them fit
- BBecause dividing always makes numbers bigger
- CBecause 1/3 is negative
- DBecause 6 × 3 is multiplication, not division
Show your work -
6Circle the letter of the best answer. Show how you know.
A detective has 6 yards of crime scene tape. She needs to mark off sections that are each 1/3 of a yard. She wants to know how many sections she can mark. If each section were 1/2 yard instead, how many sections?
- A3
- B12
- C18
- D24
Rewrite each fractionWork it outSimplify