Curriculum›4A

Chapter 6 — worked answers and marking guidance

All chapter review and practice examination items

Chapter review solutions

Question 1 · reasoning

Are 3/6 and 12/24 equivalent? Explain.

Answer: Yes

Multiply numerator and denominator of 3/6 by the same factor 4; the represented amount is unchanged.

Question 2 · comparison

Insert <, >, or =: 1/3 ___ 2/5.

Answer: <

Rename fractions using common denominator 15 and compare equal-size parts.

Question 3 · conversion

Write 26/5 as a mixed number in simplest form.

Answer: 5 1/5

26 ÷ 5 gives 5 full wholes and 1 remaining parts of size 1/5. Simplify the fractional part to obtain 5 1/5.

Question 4 · conversion

Write 47/10 as a mixed number in simplest form.

Answer: 4 7/10

47 ÷ 10 gives 4 full wholes and 7 remaining parts of size 1/10. Simplify the fractional part to obtain 4 7/10.

Question 5 · calculation

Write 4 2/3 as an improper fraction.

Answer: 14/3

Each whole has 3 parts. 4 wholes and 2 more parts make 14 parts.

Question 6 · sharing

4 identical pies are shared equally among 8 children. What fraction of one pie does each child get?

Answer: 1/2

Divide 4 equal wholes into 8 shares: each gets 4/8 of a pie, equivalent to 1/2.

Question 7 · reasoning

Are 1/2 and 2/4 equivalent? Explain.

Answer: Yes

Multiply numerator and denominator of 1/2 by the same factor 2; the represented amount is unchanged.

Question 8 · comparison

Insert <, >, or =: 2/10 ___ 7/10.

Answer: <

Rename fractions using common denominator 10 and compare equal-size parts.

Question 9 · conversion

Write 23/4 as a mixed number in simplest form.

Answer: 5 3/4

23 ÷ 4 gives 5 full wholes and 3 remaining parts of size 1/4. Simplify the fractional part to obtain 5 3/4.

Question 10 · conversion

Write 22/10 as a mixed number in simplest form.

Answer: 2 1/5

22 ÷ 10 gives 2 full wholes and 2 remaining parts of size 1/10. Simplify the fractional part to obtain 2 1/5.

Question 11 · calculation

Write 2 1/12 as an improper fraction.

Answer: 25/12

Each whole has 12 parts. 2 wholes and 1 more parts make 25 parts.

Question 12 · sharing

3 identical pies are shared equally among 6 children. What fraction of one pie does each child get?

Answer: 1/2

Divide 3 equal wholes into 6 shares: each gets 3/6 of a pie, equivalent to 1/2.

Question 13 · reasoning

Are 1/5 and 2/10 equivalent? Explain.

Answer: Yes

Multiply numerator and denominator of 1/5 by the same factor 2; the represented amount is unchanged.

Question 14 · comparison

Insert <, >, or =: 1/8 ___ 7/8.

Answer: <

Rename fractions using common denominator 8 and compare equal-size parts.

Question 15 · conversion

Write 13/4 as a mixed number in simplest form.

Answer: 3 1/4

13 ÷ 4 gives 3 full wholes and 1 remaining parts of size 1/4. Simplify the fractional part to obtain 3 1/4.

Question 16 · conversion

Write 49/12 as a mixed number in simplest form.

Answer: 4 1/12

49 ÷ 12 gives 4 full wholes and 1 remaining parts of size 1/12. Simplify the fractional part to obtain 4 1/12.

Question 17 · calculation

Write 1 3/12 as an improper fraction.

Answer: 15/12

Each whole has 12 parts. 1 wholes and 3 more parts make 15 parts.

Question 18 · sharing

9 identical pies are shared equally among 9 children. What fraction of one pie does each child get?

Answer: 1

Divide 9 equal wholes into 9 shares: each gets 9/9 of a pie, equivalent to 1.

Question 19 · reasoning

Are 3/10 and 15/50 equivalent? Explain.

Answer: Yes

Multiply numerator and denominator of 3/10 by the same factor 5; the represented amount is unchanged.

Question 20 · comparison

Insert <, >, or =: 9/10 ___ 1/4.

Answer: >

Rename fractions using common denominator 20 and compare equal-size parts.

Question 21 · conversion

Write 19/10 as a mixed number in simplest form.

Answer: 1 9/10

19 ÷ 10 gives 1 full wholes and 9 remaining parts of size 1/10. Simplify the fractional part to obtain 1 9/10.

Question 22 · conversion

Write 16/3 as a mixed number in simplest form.

Answer: 5 1/3

16 ÷ 3 gives 5 full wholes and 1 remaining parts of size 1/3. Simplify the fractional part to obtain 5 1/3.

Question 23 · calculation

Write 1 2/6 as an improper fraction.

Answer: 8/6

Each whole has 6 parts. 1 wholes and 2 more parts make 8 parts.

Question 24 · sharing

3 identical pies are shared equally among 5 children. What fraction of one pie does each child get?

Answer: 3/5

Divide 3 equal wholes into 5 shares: each gets 3/5 of a pie, equivalent to 3/5.

Question 25 · reasoning

Are 4/12 and 20/60 equivalent? Explain.

Answer: Yes

Multiply numerator and denominator of 4/12 by the same factor 5; the represented amount is unchanged.

Question 26 · comparison

Insert <, >, or =: 2/4 ___ 6/8.

Answer: <

Rename fractions using common denominator 8 and compare equal-size parts.

Question 27 · conversion

Write 14/4 as a mixed number in simplest form.

Answer: 3 1/2

14 ÷ 4 gives 3 full wholes and 2 remaining parts of size 1/4. Simplify the fractional part to obtain 3 1/2.

Question 28 · error analysis

A student claims 2/3 equals 3/4 because the numerator and denominator each increase by 1. Explain the error.

Answer: No

Equivalent fractions multiply numerator and denominator by the same nonzero factor. 2/3 = 8/12 while 3/4 = 9/12.

Question 29 · reasoning

Two students each shade 2/5 of a rectangle, but one rectangle has twice the area of the other. Are the shaded areas necessarily equal? Explain.

Answer: No

Both shade 2/5 of their own reference whole. Because one whole has twice the area, that shaded region also has twice the area.

Question 30 · error analysis

Someone calls 7/4 seven whole numbers. Express 7/4 as a mixed number and explain.

Answer: 1 3/4

Four fourths make one whole; three fourths remain.

Question 31 · error analysis

A student says 11/3 = 3 1/3. Use groups of thirds to correct the mixed number.

Answer: 3 2/3

Eleven thirds contain three groups of three thirds with two thirds left.

Question 32 · error analysis

A student converts 2 3/5 to 5/13. Explain the mistake and provide the correct improper fraction.

Answer: 13/5

Two wholes contain ten fifths, plus three fifths gives thirteen fifths.

Question 33 · reasoning

Three equal pies are shared equally among four people. What fraction of a pie does each person get, and why?

Answer: 3/4

Divide each pie into fourths: there are twelve fourths total, shared in groups of three fourths.

Practice examination solutions and scoring

Question 1 · equivalence · 2 points

Complete an equivalent fraction: 1/4 = ?/20.

Answer: 5

The denominator was multiplied by 5, so the numerator must also be multiplied by 5.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 2 · comparison · 2 points

Insert <, >, or =: 1/3 ___ 4/8.

Answer: <

Rename fractions using common denominator 24 and compare equal-size parts.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 3 · conversion · 2 points

Write 21/6 as a mixed number in simplest form.

Answer: 3 1/2

21 ÷ 6 gives 3 full wholes and 3 remaining parts of size 1/6. Simplify the fractional part to obtain 3 1/2.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 4 · conversion · 2 points

Write 11/4 as a mixed number in simplest form.

Answer: 2 3/4

11 ÷ 4 gives 2 full wholes and 3 remaining parts of size 1/4. Simplify the fractional part to obtain 2 3/4.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 5 · calculation · 2 points

Write 5 1/3 as an improper fraction.

Answer: 16/3

Each whole has 3 parts. 5 wholes and 1 more parts make 16 parts.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 6 · sharing · 2 points

10 identical pies are shared equally among 7 children. What fraction of one pie does each child get?

Answer: 10/7

Divide 10 equal wholes into 7 shares: each gets 10/7 of a pie, equivalent to 10/7.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 7 · comparison · 2 points

Insert <, >, or =: 2/4 ___ 1/4.

Answer: >

Rename fractions using common denominator 4 and compare equal-size parts.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 8 · conversion · 2 points

Write 5/4 as a mixed number in simplest form.

Answer: 1 1/4

5 ÷ 4 gives 1 full wholes and 1 remaining parts of size 1/4. Simplify the fractional part to obtain 1 1/4.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 9 · conversion · 2 points

Write 23/6 as a mixed number in simplest form.

Answer: 3 5/6

23 ÷ 6 gives 3 full wholes and 5 remaining parts of size 1/6. Simplify the fractional part to obtain 3 5/6.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 10 · calculation · 2 points

Write 5 1/2 as an improper fraction.

Answer: 11/2

Each whole has 2 parts. 5 wholes and 1 more parts make 11 parts.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 11 · sharing · 2 points

5 identical pies are shared equally among 9 children. What fraction of one pie does each child get?

Answer: 5/9

Divide 5 equal wholes into 9 shares: each gets 5/9 of a pie, equivalent to 5/9.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 12 · equivalence · 2 points

Complete an equivalent fraction: 2/5 = ?/10.

Answer: 4

The denominator was multiplied by 2, so the numerator must also be multiplied by 2.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 13 · conversion · 2 points

Write 17/3 as a mixed number in simplest form.

Answer: 5 2/3

17 ÷ 3 gives 5 full wholes and 2 remaining parts of size 1/3. Simplify the fractional part to obtain 5 2/3.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 14 · conversion · 2 points

Write 17/8 as a mixed number in simplest form.

Answer: 2 1/8

17 ÷ 8 gives 2 full wholes and 1 remaining parts of size 1/8. Simplify the fractional part to obtain 2 1/8.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 15 · calculation · 2 points

Write 3 3/12 as an improper fraction.

Answer: 39/12

Each whole has 12 parts. 3 wholes and 3 more parts make 39 parts.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 16 · sharing · 2 points

7 identical pies are shared equally among 3 children. What fraction of one pie does each child get?

Answer: 7/3

Divide 7 equal wholes into 3 shares: each gets 7/3 of a pie, equivalent to 7/3.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 17 · equivalence · 2 points

Complete an equivalent fraction: 2/3 = ?/9.

Answer: 6

The denominator was multiplied by 3, so the numerator must also be multiplied by 3.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 18 · ordering · 2 points

Order these fractions from least to greatest: 1/3, 4/5, 7/8.

Answer: 1/3, 4/5, 7/8

Rename all three fractions using a common denominator, then compare numerators for equal-size parts.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 19 · conversion · 2 points

Write 9/2 as a mixed number in simplest form.

Answer: 4 1/2

9 ÷ 2 gives 4 full wholes and 1 remaining parts of size 1/2. Simplify the fractional part to obtain 4 1/2.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 20 · calculation · 2 points

Write 1 3/10 as an improper fraction.

Answer: 13/10

Each whole has 10 parts. 1 wholes and 3 more parts make 13 parts.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 21 · sharing · 2 points

7 identical pies are shared equally among 4 children. What fraction of one pie does each child get?

Answer: 7/4

Divide 7 equal wholes into 4 shares: each gets 7/4 of a pie, equivalent to 7/4.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 22 · equivalence · 2 points

Complete an equivalent fraction: 4/5 = ?/15.

Answer: 12

The denominator was multiplied by 3, so the numerator must also be multiplied by 3.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 23 · comparison · 2 points

Insert <, >, or =: 1/3 ___ 3/6.

Answer: <

Rename fractions using common denominator 6 and compare equal-size parts.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 24 · conversion · 2 points

Write 53/12 as a mixed number in simplest form.

Answer: 4 5/12

53 ÷ 12 gives 4 full wholes and 5 remaining parts of size 1/12. Simplify the fractional part to obtain 4 5/12.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 25 · calculation · 2 points

Write 2 1/2 as an improper fraction.

Answer: 5/2

Each whole has 2 parts. 2 wholes and 1 more parts make 5 parts.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 26 · sharing · 2 points

7 identical pies are shared equally among 5 children. What fraction of one pie does each child get?

Answer: 7/5

Divide 7 equal wholes into 5 shares: each gets 7/5 of a pie, equivalent to 7/5.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 27 · reasoning · 3 points

Are 2/3 and 10/15 equivalent? Explain.

Answer: Yes

Multiply numerator and denominator of 2/3 by the same factor 5; the represented amount is unchanged.

Scoring (3 points): Award one point for identifying the quantities or relationship, one for the correct method, and one for a correct justified result.

Question 28 · reasoning · 2 points

Are 3/4 and 15/20 equivalent? Explain.

Answer: Yes

Multiply numerator and denominator of 3/4 by the same factor 5; the represented amount is unchanged.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 29 · reasoning · 4 points

Two students each shade 3/5 of a rectangle, but one rectangle has twice the area of the other. Are the shaded areas necessarily equal? Explain.

Answer: No

Both shade 3/5 of their own reference whole. Because one whole has twice the area, that shaded region also has twice the area.

Scoring (4 points): Award one point for a sound method and one for the correct result.

Question 30 · conversion · 2 points

Write 42/12 as a mixed number in simplest form.

Answer: 3 1/2

42 ÷ 12 gives 3 full wholes and 6 remaining parts of size 1/12. Simplify the fractional part to obtain 3 1/2.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 31 · conversion · 2 points

Write 29/8 as a mixed number in simplest form.

Answer: 3 5/8

29 ÷ 8 gives 3 full wholes and 5 remaining parts of size 1/8. Simplify the fractional part to obtain 3 5/8.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 32 · calculation · 2 points

Write 5 1/4 as an improper fraction.

Answer: 21/4

Each whole has 4 parts. 5 wholes and 1 more parts make 21 parts.

Scoring (2 points): Award one point for a sound method and one for the correct result.

Question 33 · sharing · 2 points

8 identical pies are shared equally among 4 children. What fraction of one pie does each child get?

Answer: 2

Divide 8 equal wholes into 4 shares: each gets 8/4 of a pie, equivalent to 2.

Scoring (2 points): Award one point for a sound method and one for the correct result.