All questions
Question 1
Which equation represents 87 as a multiple of the unit fraction 81?
- 87=8×(81)
- 87=7+(81)
- 87=87×(81)
- 87=7×(81) (correct answer)
Explanation: The fraction 7/8 means 7 copies of the unit fraction 1/8, so the equation 7/8 = 7 x (1/8) is correct. Choice A multiplies by 8 instead of 7, which gives a whole number, not 7/8. Choice B shows addition rather than multiplication, so it does not match the required form. Choice C multiplies 7/8 by 1/8 instead of multiplying a whole number by 1/8, so it does not represent the fraction correctly.
Question 2
Which repeated addition matches the multiplication equation 54=4×(51)?
- 54=51+51+51+51 (correct answer)
- 54=51+51+51+51+51
- 54=4+51
- 54=54+51
Explanation: This question tests 4th grade understanding that a fraction a/b is a multiple of 1/b, represented as a/b = a × (1/b) using visual fraction models (CCSS.4.NF.4.a). Any fraction can be thought of as a whole number multiple of its unit fraction—the unit fraction is the fraction with 1 in the numerator (like 1/4, 1/8, 1/5). For example, 5/4 means '5 fourths,' which is the same as '5 times 1/4' or '5 copies of 1/4.' The equation form is a/b = a × (1/b), where the numerator (a) tells how many unit fractions (1/b) we have. To represent 4/5 as a multiple of 1/5, we recognize that 4/5 contains 4 copies of 1/5, so the repeated addition is 1/5 + 1/5 + 1/5 + 1/5 = 4/5, matching 4 × (1/5). Choice A is correct because it shows 1/5 added 4 times to equal 4/5, demonstrating understanding that fractions are built from unit fractions—4/5 is simply 4 of the 1/5 pieces. Choice B represents adding one extra unit fraction, which happens when students miscount the number of additions needed. To help students: Use visual models—draw 4 individual 1/5-size pieces, show adding them gives 4/5. Emphasize: the numerator tells how many times to add the unit fraction in repeated addition.
Question 3
A recipe uses 41 cup of milk per serving. Amir makes 6 servings. Which equation shows the total milk as a multiple of the unit fraction 41? (Multiplication means repeated addition of 41.)
- 46=6+(41)
- 46=4×(41)
- 46=6×(41) (correct answer)
- 46=46×(41)
Explanation: Since Amir makes 6 servings and each serving uses 1/4 cup, the total is 6 times 1/4, which matches Choice C. Choice A shows 6 plus 1/4 instead of 6 times 1/4, which does not represent repeated addition of the unit fraction 6 times. Choice B shows 4 times 1/4, using the wrong number of servings. Choice D multiplies 6/4 by 1/4 again, which does not represent the total milk used across the 6 servings at all. Multiplying the number of servings by the unit fraction shows the total amount of milk as repeated addition of 1/4.
Question 4
How many unit fractions 81 are in the fraction 83?
- 3 (correct answer)
- 24
- 1
- 8
Explanation: The correct answer is A, 3. The fraction 3/8 is made of 3 copies of the unit fraction 1/8. Choice B, 24, comes from multiplying the numerator and denominator together instead of just counting the copies. Choice C, 1, comes from thinking there is only one unit fraction instead of counting how many eighths are in 3/8. Choice D, 8, comes from using the denominator itself instead of the numerator, which tells how many copies there are.
Question 5
Marcus wants to show that the unit fraction 91 is the building block for 92. Complete: 92=×(91).
- 9
- 92
- 18
- 2 (correct answer)
Explanation: The correct answer is D, 2, because 92 is made of 2 copies of the unit fraction 91. Choice A, 9, is just the denominator, not the number of copies. Choice B, 92, restates the target fraction instead of finding the multiplier. Choice C, 18, comes from multiplying the numerator and denominator together instead of comparing them. Question 6
Keisha is counting by unit fractions: 31,32,33,34. What number times 31 equals 34?
- 1
- 4 (correct answer)
- 3
- 12
Explanation: The correct answer is B, 4, because 4/3 is made of 4 copies of the unit fraction 1/3, so 4 times 1/3 equals 4/3. Choice A, 1, comes from thinking only one copy is needed. Choice C, 3, comes from using the denominator instead of the numerator. Choice D, 12, comes from multiplying the numerator and denominator together instead of just counting the copies.
Question 7
Yuki draws fraction bars to show 78 as 8 copies of the unit fraction 71. Which equation matches her model?
- 78=7×(71)
- 78=8+(71)
- 78=56×(71)
- 78=8×(71) (correct answer)
Explanation: The correct answer is D. Yuki's model shows 8 equal copies of the unit fraction 1/7, which matches the equation 8/7 = 8 times 1/7. Choice A uses 7 copies instead of 8, which does not match her model. Choice B combines the copies with addition instead of multiplication. Choice C uses 56, which does not represent the number of unit fractions described in the model.
Question 8
Which statement correctly describes 49 as a multiple of a unit fraction?
- The model shows 49=9×41 with 9 fourth-parts shaded (correct answer)
- The model shows 94=4×91 with 4 ninth-parts shaded
- The model shows 49=4×91 with 4 ninth-parts shaded
- The model shows 94=9×41 with 9 fourth-parts shaded
Explanation: The fraction 49 is made of 9 copies of the unit fraction 41, so it equals 9×41. Choice B describes a completely different fraction, 94, built from ninth-parts instead. Choice C mismatches the fraction 49 with the wrong unit fraction and count. Choice D also mismatches the fraction 94 with fourth-parts instead of ninth-parts. Only Choice A correctly pairs 49 with 9 copies of 41. Question 9
The number line shows points representing unit fractions and their multiples. Point R represents 1/6, and point S represents 5/6. Which equation correctly describes point S as a multiple of the unit fraction at point R?
- 5/6 = 5 x 1/6 because S is 5 unit lengths from 0 (correct answer)
- 5/6 = 4 x 1/6 because there are 4 spaces between R and S
- 5/6 = 6 x 1/6 because the denominator tells us the multiplier
- 5/6 = 4/6 x 1/6 because S is 4/6 units away from R
Explanation: Point S at 5/6 is 5 unit lengths of 1/6 away from 0, so 5/6 = 5 x 1/6. Choice B describes a true distance (4 spaces between R and S) but pairs it with the wrong equation, since that distance is measured from R rather than from 0. Choice C uses the denominator itself as the multiplier, which doesn't relate to the actual position of S. Choice D creates an equation that doesn't represent a valid unit-fraction multiple.
Question 10
Look at the equation: 914=14×91. Which equation correctly follows the same pattern using 417?
- 417=17+41
- 417=17×41 (correct answer)
- 417=21×41
- 417=4×171
Explanation: 17×41 is correct because it follows the same pattern as the example, multiplying the numerator by the unit fraction. The addition choice is incorrect because it uses the wrong operation. 21×41 is incorrect because 21 does not match the numerator 17. 4×171 is incorrect because it swaps the numerator and denominator. Question 11
Ana is working with the fraction 712. She correctly writes it as 12×71. Her teacher asks her to also express this same fraction as a multiple of 73. What should Ana write?
- 712=74×73
- 712=3×73
- 712=36×73
- 712=4×73 (correct answer)
Explanation: Since 712 is made of 4 copies of 73 (because 4×3=12), the correct expression is 4×73. Choice A incorrectly multiplies two fractions together instead of a whole number by a fraction. Choice B uses the wrong whole number, which would only account for 79, not 712. Choice C uses a whole number far too large, which would produce a much bigger fraction than 712. Choice D correctly identifies 4 as the number of 73 pieces that make up 712. Question 12
Maria is making a recipe that calls for 7/3 cups of flour. She wants to understand this amount by thinking about it as unit fractions. If she measures the flour using 1/3-cup scoops, how many scoops will she need, and which equation represents this relationship?
- She needs 7 scoops, and 7/3 = 7 x 1/3 (correct answer)
- She needs 3 scoops, and 7/3 = 3 x 1/7
- She needs 10 scoops, and 7/3 = 10 x 1/3
- She needs 21 scoops, and 7/3 = 7 x 3 x 1/3
Explanation: Dividing 7/3 by 1/3 shows how many 1/3-cup scoops fit into 7/3 cups, which is 7 scoops, written as 7/3 = 7 x 1/3. Choice B (3 scoops) inverts the numerator and denominator in the equation. Choice C (10 scoops) doesn't match the division at all. Choice D (21 scoops) multiplies by an extra factor of 3 that isn't part of the relationship.
Question 13
On the number line, each jump is the unit fraction 61. Starting at 0, Jamal makes 5 equal jumps to land on 65. Complete the statement: 65 is how many times 61?
- 65
- 30
- 6
- 5 (correct answer)
Explanation: 5 is correct because 65 is made of 5 jumps of 61, so 65=5×61. 65 is incorrect because it repeats the fraction itself instead of counting the jumps. 30 is incorrect because it multiplies the numerator and denominator together instead of reading the numerator. 6 is incorrect because it uses the denominator instead of the numerator. Question 14
On the number line, each jump is the unit fraction 1/6. After 7 equal jumps from 0, you land on 7/6. Which equation shows 7/6 as a multiple of the unit fraction 1/6?
- 7/6 = 7 + (1/6)
- 7/6 = (7/6) × (1/6)
- 7/6 = 6 × (1/6)
- 7/6 = 7 × (1/6) (correct answer)
Explanation: Seven jumps of 1/6 each means 7/6 is seven copies of the unit fraction, written as 7 x (1/6). Choice A adds instead of multiplying. Choice C uses 6 jumps instead of 7. Choice B multiplies the target fraction by itself rather than by the unit fraction.
Question 15
Complete: 127=×(121). The unit fraction 121 is the building block.
- 1
- 84
- 12
- 7 (correct answer)
Explanation: Since 7/12 is made of 7 copies of the unit fraction 1/12, the missing number is 7, making Choice D correct. Choice A, 1, would only represent a single copy of the unit fraction, not seven. Choice B, 84, comes from multiplying 7 by 12 instead of recognizing 7 as the number of unit fractions. Choice C, 12, mistakes the denominator of the unit fraction itself for the number of copies needed.
Question 16
Chen shades 6 equal parts of a shape divided into 11 equal parts. That is 116. Which equation shows this fraction as 6 copies of the unit fraction 111?
- 116=66×(111)
- 116=6×(111) (correct answer)
- 116=116×(111)
- 116=11×(111)
Explanation: This question tests 4th grade understanding that a fraction a/b is a multiple of 1/b, represented as a/b = a × (1/b) using visual fraction models (CCSS.4.NF.4.a). Any fraction can be thought of as a whole number multiple of its unit fraction—the unit fraction is the fraction with 1 in the numerator (like 1/4, 1/8, 1/5). For example, 5/4 means '5 fourths,' which is the same as '5 times 1/4' or '5 copies of 1/4.' The equation form is a/b = a × (1/b), where the numerator (a) tells how many unit fractions (1/b) we have. To represent 6/11 as a multiple of 1/11, we recognize that 6/11 contains 6 copies of 1/11, so the equation is 6/11 = 6 × (1/11), and the shaded model shows 6 individual 1/11 pieces making 6/11. Choice B is correct because the equation shows 6 × (1/11) = 6/11, where the numerator 6 is the number of 1/11 units in 6/11, demonstrating understanding that fractions are built from unit fractions—6/11 is simply 6 of the 1/11 pieces. Choice A represents using the denominator as the multiplier, which happens when students confuse numerator and denominator roles. To help students: Use visual models—draw a shape divided into 11 equal parts, shade 6 to show 6/11 as 6 copies of 1/11. Emphasize: the numerator tells how many unit fractions, the denominator tells which unit fraction (elevenths).
Question 17
Which equation represents 1210 as a product of a whole number and the unit fraction 121?
- 1210=10+(121)
- 1210=120×(121)
- 1210=10×(121) (correct answer)
- 1210=12×(121)
Explanation: The fraction 10/12 means 10 copies of the unit fraction 1/12, so 10 x (1/12) is correct. Choice A shows addition instead of multiplication. Choice B multiplies by 120, a number far too large to represent this fraction. Choice D uses 12, the denominator, as the multiplier instead of 10, the numerator.
Question 18
Sofia writes 43 as repeated addition of the unit fraction 41: 41+41+41. Which equation matches this as multiplication?
- 43=1×(41)
- 43=12×(41)
- 43=3×(41) (correct answer)
- 43=4×(41)
Explanation: 3×41 is correct because Sofia added three copies of 41. 1×41 is incorrect because it counts only one jump instead of three. 12×41 is incorrect because it multiplies the numerator and denominator together instead of counting the addends. 4×41 is incorrect because it uses the denominator as the count instead of the number of addends. Question 19
Each serving is the unit fraction 61 of a cup. Jamal uses 68 of a cup. Complete the equation: 68=×(61).
- 68
- 48
- 8 (correct answer)
- 6
Explanation: The correct answer is 8, because 8/6 is made up of 8 copies of the unit fraction 1/6. Choice A, 8/6, restates the original fraction instead of finding how many sixths it takes to build it. Choice B, 48, comes from multiplying 8 and 6 instead of recognizing the numerator as the count of unit fractions. Choice D, 6, mistakenly uses the denominator instead of the numerator.
Question 20
Students are comparing two ways to express 815. Emma says it equals 15×81, and Marcus says it equals 215×41. Who is correct?
- Only Emma is correct because 815 can only be written as 15×81
- Only Marcus is correct because 215×41=815 and this is the proper form
- Both are correct because 15×81=815 and 215×41=815 (correct answer)
- Neither is correct because 815 should be written as 8×115 instead
Explanation: Both Emma and Marcus are correct. Emma's way, 15 times 1/8, means taking 15 copies of one-eighth, which equals 15/8. Marcus's way, 15/2 times 1/4, first finds half of 15 as 15/2, then splits that in fourths, and this also equals 15/8. Choice A is wrong because it ignores that Marcus's method also produces 15/8. Choice B is wrong because it ignores that Emma's simpler method is equally valid.