Divide Fractions by Fractions - 6th Grade Math
- Three friends share pound of trail mix equally. How much does each friend get? Write the division expression and compute . Verify by multiplying your answer by 3. Answer: lb each; and This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), interpreting in contexts like sharing among friends, and understanding via visual models and the multiplication-division relationship. Dividing fractions: (1/2)÷3=(1/2)×(1/3)=1/6 (treat 3 as 3/1, flip to reciprocal, multiply). Verification: divisor×quotient=dividend (3×(1/6)=3/6=1/2 confirms quotient correct). Context: 'how much trail mix each of 3 friends gets from 1/2 lb' divides: 1/2÷3=1/6 lb each. Multiplication-division relationship: (1/2)÷3=1/6 because 3 times (1/6) equals (1/2) (3×1/6=1/2, division is inverse of multiplication). The correct choice is A, which uses the reciprocal method to get 1/6 and verifies correctly. Common errors include treating division incorrectly, like getting 3/2 as in B.
- A recipe uses cup of yogurt. Each smoothie serving needs cup of yogurt. How many servings can you make from cup? Compute and interpret the result (is it more or less than 1 full serving?). Then verify your answer by multiplying: . Answer: of a serving (less than 1); and This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), interpreting in contexts like servings, sharing, or rectangle area÷length=width, and understanding via visual models and the multiplication-division relationship. Dividing fractions: (2/3)÷(3/4)=(2/3)×(4/3)=8/9 (flip divisor to reciprocal, multiply). Verification: divisor×quotient=dividend ((3/4)×(8/9)=24/36=2/3 confirms quotient correct). Context: 'how many 3/4-cup servings in 2/3 cup yogurt?' divides: 2/3÷3/4=8/9 (less than 1 full serving, 8/9 of a 3/4-cup portion). Multiplication-division relationship: (2/3)÷(3/4)=8/9 because (3/4) of (8/9) equals (2/3) (3/4×8/9=24/36=2/3, division is inverse of multiplication). The correct choice is B, which uses the reciprocal method to get 8/9 and verifies correctly. Common errors include multiplying instead of dividing ((2/3)×(3/4)=1/2 as in A), or flipping the wrong fraction leading to incorrect quotients like in D.
- A ribbon is yard long. Each bracelet needs yard of ribbon. The division expression is . How many bracelets can be made from the ribbon? (Simplify.) Answer: This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method, interpreting in contexts like how many segments of one length fit into another, and understanding via visual models and the multiplication-division relationship. To divide (3/4)÷(1/2), flip the divisor to its reciprocal and multiply: (3/4) × (2/1) = 6/4 = 3/2, so 3/2 bracelets can be made. Verification: multiply divisor by quotient to get dividend, (1/2) × (3/2) = 3/4, which confirms. For example, a ribbon of 3/4 yard divided by 1/2 yard per bracelet: (3/4) × 2 = 3/2, meaning 1 full and half another. The correct division using the reciprocal gives simplified 3/2. Common mistakes include subtracting fractions or not simplifying 6/4. Method: write division, flip divisor, multiply, reduce fraction, verify.
- A recipe uses cup of yogurt. One serving size is cup. How many -cup servings can you make from cup? Compute and choose the best interpretation. Answer: of a serving (less than 1 full -cup serving) This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), interpreting in contexts like servings from a given amount of yogurt. To divide (2/3)÷(3/4), flip the divisor to its reciprocal 4/3 and multiply: (2/3)×(4/3)=(2×4)/(3×3)=8/9. Verification: multiply the divisor by the quotient, (3/4)×(8/9)=(3×8)/(4×9)=24/36=2/3, which matches the dividend. In context, this means you can make 8/9 of a 3/4-cup serving from 2/3 cup of yogurt, which is less than one full serving. A common error is multiplying instead of dividing, like (2/3)×(3/4)=1/2 as in choice A, or flipping the wrong fraction leading to incorrect results like 2/3 in choice C. To compute: write the division, flip the divisor, multiply numerators and denominators, simplify if needed, and verify by multiplying back. Visual models, like a bar representing 2/3 cup divided into 3/4-cup segments, show it fits 8/9 of such a segment.
- On a number line, is a point to the right of 0. If you take steps of size , how many steps reach ? This is . Which value is correct? Answer: This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), interpreted on a number line as steps to reach a point. Compute (2/3)÷(3/4)=(2/3)×(4/3)=8/9 steps. Verification: (3/4)×(8/9)=24/36=2/3, reaching the point. This is less than 1 step since 2/3 < 3/4. Mistakes include inverting the operation to get 9/8 as in choice B, or multiplying to get 1/2. Method: division to multiplication by reciprocal, compute 8/9, verify. Visual: number line with steps of 3/4 up to 2/3 fits 8/9 of a step.
- A science club has liter of solution and pours it equally into 3 identical containers. How much solution goes in each container? Compute . Answer: liter This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), here dividing by a whole number interpreted as sharing equally among containers. Compute (1/2)÷3=(1/2)×(1/3)=(1×1)/(2×3)=1/6 liter per container. Verification: multiply one share by 3, (1/6)×3=3/6=1/2 liter, matching the total. Context: sharing 1/2 liter equally into 3 parts is like finding how many 1/3 portions fit into 1/2, but directly it's division by 3. Errors include flipping incorrectly to get 3/2 as in choice A, or confusing with multiplication to get 2/3. Steps: rewrite division as multiplication by reciprocal, compute numerator and denominator, simplify, verify by multiplying back. Visual: a bar of 1/2 liter divided into 3 equal parts shows each as 1/6.
- Compute and choose the simplified result. Answer: This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), focusing on computing and simplifying the result. Compute (3/4)÷(2/3)=(3/4)×(3/2)=(3×3)/(4×2)=9/8. Verification: (2/3)×(9/8)=(2×9)/(3×8)=18/24=3/4, correct. This is greater than 1 since the dividend is larger than the divisor. Errors include flipping the wrong fraction to get 8/9 as in choice B, or multiplying directly to get 6/12=1/2. Steps: write division, reciprocal of divisor, multiply fractions, simplify 9/8 (already simplest), verify. Common example: (1/2)÷(1/4)=2 shows how many quarters in a half.
- A ribbon is yard long. Each bow needs yard of ribbon. How many bows can be made? Compute . Answer: This question tests dividing fractions using the reciprocal method (multiply by ), in context of how many items can be made from a given length. Compute bows. Verification: yard, matching the total. This means 1 full bow and half another from yard. Errors include multiplying fractions to get 3/8 as in choice A, or confusing reciprocals to get 1/2. Steps: flip divisor, multiply, simplify to , verify. Context like ribbons shows practical division application.
- Which value makes this verification true? If , then . What is ? Answer: This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), verifying through the multiplication-division relationship. To find q where (3/4)×q=2/3, q=(2/3)÷(3/4)=(2/3)×(4/3)=8/9. Verification: (3/4)×(8/9)=24/36=2/3, correct. This confirms division as the inverse of multiplication. Common errors: flipping incorrectly to 9/8 as in choice D, or multiplying to 1/2. Method: solve for q using reciprocal, compute, verify by plugging back. Examples like (1/2)÷(1/4)=2 verify similarly.
- A recipe needs cup of yogurt. You have a scoop that holds cup. The division expression is . How many full scoops of size cup fit into cup of yogurt? (Choose the simplified value.) Answer: This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method, interpreting in contexts like servings or how many scoops of one size fit into another amount, and understanding via visual models and the multiplication-division relationship. To divide (2/3)÷(3/4), flip the divisor to its reciprocal and multiply: (2/3) × (4/3) = 8/9, meaning 8/9 of a full 3/4-cup scoop fits into 2/3 cup of yogurt. Verification: multiply divisor by quotient to get dividend, (3/4) × (8/9) = 24/36 = 2/3, which confirms the result. For example, imagine a bar representing 2/3 cup; dividing it into 3/4-cup segments shows it fits 8/9 of one segment. The correct method is to use the reciprocal for division, yielding 8/9 as the simplified value. A common mistake is multiplying without flipping, like (2/3) × (3/4) = 1/2, or flipping the wrong fraction. Remember the steps: write the division, flip the divisor, multiply, simplify, and verify with multiplication.
- A road segment is mile long. A student walks at a pace of mile per minute. The time (in minutes) is . How many minutes does it take? (Simplify.) Answer: This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method, interpreting in contexts like time taken to cover distance at a given speed, and understanding via visual models and the multiplication-division relationship. To divide (1/2)÷(1/4), flip the divisor to its reciprocal and multiply: (1/2) × (4/1) = 4/2 = 2, so it takes 2 minutes. Verification: multiply divisor by quotient to get dividend, (1/4) × 2 = 1/2, which confirms. For example, distance 1/2 mile at 1/4 mile per minute: how many quarters in a half is 2. The correct division using the reciprocal gives 2. A common mistake is adding fractions or using wrong reciprocal. Method: write division, flip divisor, multiply, simplify, verify with multiplication.
- A rectangular garden has area square mile and length mile. The width is found by . What is the width (in miles), simplified? Answer: This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method, interpreting in contexts like finding the width of a rectangle given area and length, and understanding via visual models and the multiplication-division relationship. To divide (1/2)÷(3/4), flip the divisor to its reciprocal and multiply: (1/2) × (4/3) = 4/6 = 2/3, so the width is 2/3 mile. Verification: multiply divisor by quotient to get dividend, (3/4) × (2/3) = 6/12 = 1/2, which matches the area. For example, a rectangle with area 1/2 square mile and length 3/4 mile has width (1/2) × (4/3) = 2/3 mile. The correct division using the reciprocal gives the simplified 2/3. A common error is dividing numerators and denominators separately, like 1÷3 / 2÷4 = 1/3 / 1/2 = 2/3 incorrectly, or arithmetic mistakes. Steps: write division, flip divisor, multiply, simplify 4/6 to 2/3, verify with multiplication.
- Use the multiplication-division relationship to check a quotient: If which multiplication correctly verifies the result (divisor quotient dividend)? Answer: This question tests dividing fractions using the reciprocal method, emphasizing the multiplication-division relationship for verification, and understanding via contexts and visual models. The division is verified by multiplying divisor by quotient to equal dividend: . Other options like do not verify correctly. For example, the relationship shows division is the inverse of multiplication, so if quotient is correct, divisor quotient dividend. The correct verification is option B. A common error is confusing which to multiply, like quotient dividend. Remember: to check, always multiply divisor by proposed quotient and see if it equals dividend.
- Number-line reasoning: On a number line, is one step size. How many -steps are in ? Compute and verify by multiplication. Answer: step; and This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), interpreting in number-line contexts like step sizes, and understanding via visual models and the multiplication-division relationship. Dividing fractions: (1/3)÷(3/4)=(1/3)×(4/3)=4/9 (flip divisor to reciprocal, multiply). Verification: divisor×quotient=dividend ((3/4)×(4/9)=12/36=1/3 confirms quotient correct). Context: 'how many 3/4-steps in 1/3' divides: 1/3÷3/4=4/9 step (less than 1). Multiplication-division relationship: (1/3)÷(3/4)=4/9 because (3/4) of (4/9) equals (1/3) (3/4×4/9=1/3, division is inverse of multiplication). The correct choice is A, which uses the reciprocal method to get 4/9 and verifies correctly. Common errors include flipping the wrong fraction, leading to 9/4 as in B.
- A painter has gallon of paint. One room needs gallon. How many rooms can be painted? Compute and verify by multiplication. Answer: rooms; and This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), interpreting in contexts like painting rooms, and understanding via visual models and the multiplication-division relationship. Dividing fractions: (2/3)÷(1/3)=(2/3)×(3/1)=2 (flip divisor to reciprocal, multiply). Verification: divisor×quotient=dividend ((1/3)×2=2/3 confirms quotient correct). Context: 'how many rooms needing 1/3 gallon from 2/3 gallon' divides: 2/3÷1/3=2 rooms. Multiplication-division relationship: (2/3)÷(1/3)=2 because (1/3) of 2 equals (2/3) (1/3×2=2/3, division is inverse of multiplication). The correct choice is B, which uses the reciprocal method to get 2 and verifies correctly. Common errors include wrong division, like getting 3/2 as in C.
- Compute and interpret: A container holds liter of juice. Each small bottle holds liter. How many small bottles can be filled? Compute and verify by multiplying the quotient by . Answer: bottles; and This question tests dividing fractions using the reciprocal method (multiply by ), interpreting in contexts like filling bottles, and understanding via visual models and the multiplication-division relationship. Dividing fractions: (flip divisor to reciprocal, multiply). Verification: divisor quotient dividend confirms quotient correct). Context: 'how many -liter bottles from liter' divides: (1.5 bottles). Multiplication-division relationship: because of equals (, division is inverse of multiplication). The correct choice is C, which uses the reciprocal method to get and verifies correctly. Common errors include multiplying instead of dividing, like getting as in B.
- A science class has cup of saltwater. Each test tube needs cup. How many test tubes can be filled? Compute and verify by multiplication. Answer: test tubes; and This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), interpreting in contexts like filling test tubes, and understanding via visual models and the multiplication-division relationship. Dividing fractions: (3/4)÷(2/3)=(3/4)×(3/2)=9/8 (flip divisor to reciprocal, multiply). Verification: divisor×quotient=dividend ((2/3)×(9/8)=18/24=3/4 confirms quotient correct). Context: 'how many 2/3-cup test tubes from 3/4 cup' divides: 3/4÷2/3=9/8 (more than 1). Multiplication-division relationship: (3/4)÷(2/3)=9/8 because (2/3) of (9/8) equals (3/4) (2/3×9/8=3/4, division is inverse of multiplication). The correct choice is B, which uses the reciprocal method to get 9/8 and verifies correctly. Common errors include incorrect multiplication, like getting 8/9 as in A.
- A rectangle has area square mile and length mile. What is the width? Compute . Answer: mile This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), interpreting in contexts like finding the width of a rectangle given area and length. To find the width, compute (1/2)÷(3/4)=(1/2)×(4/3)=(1×4)/(2×3)=4/6=2/3 mile. Verification: multiply length by width, (3/4)×(2/3)=(3×2)/(4×3)=6/12=1/2 square mile, matching the area. This uses the area formula where area = length × width, so width = area ÷ length, the inverse of multiplication. Common errors include multiplying instead of dividing to get 3/8 as in choice B, or arithmetic slips like not simplifying 4/6 correctly. Method: write the division, flip the divisor, multiply, simplify the fraction, and verify. Visual aids like drawing a rectangle with area 1/2 and length 3/4 help see the width as 2/3.
- Maria has of a yard of fabric. She wants to cut it into pieces that are each of a yard long to make bookmarks. After cutting all possible pieces, she realizes she made an error and each bookmark actually needs of a yard of fabric. How many complete bookmarks can she make with her original yard of fabric? Answer: 4 bookmarks because To find how many -yard bookmarks can be made from yard, we calculate . Since we can only make complete bookmarks, the answer is 4. Choice A incorrectly assumes the previously cut pieces can be reused. Choice C uses the wrong division (by instead of ). Choice D incorrectly rounds up when we need complete bookmarks.
- Use a visual model idea: Imagine a bar showing of a whole. Each group is of a whole. How many -size groups fit into ? Compute and verify by multiplication. Answer: groups; and This question tests dividing fractions (a/b)÷(c/d) using the reciprocal method (multiply by d/c), interpreting in visual model contexts like fitting groups into a bar, and understanding via visual models and the multiplication-division relationship. Dividing fractions: (2/3)÷(1/4)=(2/3)×(4/1)=8/3 (flip divisor to reciprocal, multiply). Verification: divisor×quotient=dividend ((1/4)×(8/3)=8/12=2/3 confirms quotient correct). Context: 'how many 1/4-size groups in 2/3' divides: 2/3÷1/4=8/3 (more than 2 groups). Multiplication-division relationship: (2/3)÷(1/4)=8/3 because (1/4) of (8/3) equals (2/3) (1/4×8/3=2/3, division is inverse of multiplication). The correct choice is B, which uses the reciprocal method to get 8/3 and verifies correctly. Common errors include wrong reciprocal or simplification, like getting 1/6 as in C.