Curriculum›4B›Chapter 17

Chapter 17: worked solutions and marking guide

35 review answers and 35 exam answers

Chapter review solutions

Question 1 · reasoning

A 10 cm by 8 cm by 14 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Question 2 · net

A cuboid measures 4 cm by 2 cm by 6 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 4×2 faces, two 4×6 faces, two 2×6 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

4×62×64×62×64×24×2
Question 3 · edges

A cuboid has side lengths 3 cm, 5 cm and 5 cm. Find the combined length of all twelve edges.

Answer: 52 cm

There are four of each dimension. Total = 4×(3+5+5)=52 cm.

Question 4 · reasoning

A 12 cm by 8 cm by 7 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Question 5 · net

A cuboid measures 3 cm by 4 cm by 6 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 3×4 faces, two 3×6 faces, two 4×6 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

3×64×63×64×63×43×4
Question 6 · edges

A cuboid has side lengths 6 cm, 6 cm and 8 cm. Find the combined length of all twelve edges.

Answer: 80 cm

There are four of each dimension. Total = 4×(6+6+8)=80 cm.

Question 7 · reasoning

A 13 cm by 6 cm by 15 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Question 8 · construction

Draw one connected, foldable six-face net of a 6 cm by 5 cm by 2 cm cuboid. Label each face with its dimensions.

Draw and label a foldable net
Answer: A valid connected six-face net: Two 6×5 faces, two 6×2 faces, two 5×2 faces

One valid arrangement uses a connected strip of four side faces, plus two matching end faces attached without overlap. Other foldable nets are also correct.

6×25×26×25×26×56×5
Question 9 · edges

A cuboid has side lengths 6 cm, 7 cm and 8 cm. Find the combined length of all twelve edges.

Answer: 84 cm

There are four of each dimension. Total = 4×(6+7+8)=84 cm.

Question 10 · reasoning

A 5 cm by 16 cm by 4 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Question 11 · construction

Draw one connected, foldable six-face net of a 5 cm by 3 cm by 2 cm cuboid. Label each face with its dimensions.

Draw and label a foldable net
Answer: A valid connected six-face net: Two 5×3 faces, two 5×2 faces, two 3×2 faces

One valid arrangement uses a connected strip of four side faces, plus two matching end faces attached without overlap. Other foldable nets are also correct.

5×23×25×23×25×35×3
Question 12 · edges

A cuboid has side lengths 4 cm, 3 cm and 6 cm. Find the combined length of all twelve edges.

Answer: 52 cm

There are four of each dimension. Total = 4×(4+3+6)=52 cm.

Question 13 · reasoning

A 12 cm by 3 cm by 10 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Question 14 · net

A cuboid measures 3 cm by 5 cm by 4 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 3×5 faces, two 3×4 faces, two 5×4 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

3×45×43×45×43×53×5
Question 15 · edges

A cuboid has side lengths 3 cm, 4 cm and 8 cm. Find the combined length of all twelve edges.

Answer: 60 cm

There are four of each dimension. Total = 4×(3+4+8)=60 cm.

Question 16 · reasoning

A 4 cm by 3 cm by 15 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Question 17 · net

A cuboid measures 4 cm by 3 cm by 6 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 4×3 faces, two 4×6 faces, two 3×6 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

4×63×64×63×64×34×3
Question 18 · edges

A cuboid has side lengths 5 cm, 7 cm and 8 cm. Find the combined length of all twelve edges.

Answer: 80 cm

There are four of each dimension. Total = 4×(5+7+8)=80 cm.

Question 19 · reasoning

A 15 cm by 11 cm by 5 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Question 20 · net

A cuboid measures 4 cm by 5 cm by 6 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 4×5 faces, two 4×6 faces, two 5×6 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

4×65×64×65×64×54×5
Question 21 · edges

A cuboid has side lengths 5 cm, 8 cm and 4 cm. Find the combined length of all twelve edges.

Answer: 68 cm

There are four of each dimension. Total = 4×(5+8+4)=68 cm.

Question 22 · reasoning

A 4 cm by 17 cm by 9 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Question 23 · net

A cuboid measures 5 cm by 2 cm by 3 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 5×2 faces, two 5×3 faces, two 2×3 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

5×32×35×32×35×25×2
Question 24 · edges

A cuboid has side lengths 5 cm, 5 cm and 5 cm. Find the combined length of all twelve edges.

Answer: 60 cm

There are four of each dimension. Total = 4×(5+5+5)=60 cm.

Question 25 · reasoning

A 10 cm by 3 cm by 21 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Question 26 · construction

Draw one connected, foldable six-face net of a 4 cm by 3 cm by 6 cm cuboid. Label each face with its dimensions.

Draw and label a foldable net
Answer: A valid connected six-face net: Two 4×3 faces, two 4×6 faces, two 3×6 faces

One valid arrangement uses a connected strip of four side faces, plus two matching end faces attached without overlap. Other foldable nets are also correct.

4×63×64×63×64×34×3
Question 27 · edges

A cuboid has side lengths 3 cm, 5 cm and 7 cm. Find the combined length of all twelve edges.

Answer: 60 cm

There are four of each dimension. Total = 4×(3+5+7)=60 cm.

Question 28 · reasoning

A 14 cm by 9 cm by 17 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Question 29 · net

A cuboid measures 3 cm by 4 cm by 2 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 3×4 faces, two 3×2 faces, two 4×2 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

3×24×23×24×23×43×4
Question 30 · edges

A cuboid has side lengths 2 cm, 8 cm and 7 cm. Find the combined length of all twelve edges.

Answer: 68 cm

There are four of each dimension. Total = 4×(2+8+7)=68 cm.

Question 31 · reasoning

A 3 cm by 16 cm by 17 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Question 32 · net

A cuboid measures 2 cm by 6 cm by 3 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 2×6 faces, two 2×3 faces, two 6×3 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

2×36×32×36×32×62×6
Question 33 · reasoning

A 9 cm by 16 cm by 16 cm cuboid has how many faces, edges, and vertices? Explain or sketch the mathematical relationship.

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points. State which quantities or geometric properties justify the method.

Question 34 · reasoning

A learner draws six correct rectangles for a 4×6×3 cuboid but leaves them as six unconnected pieces. Is that a complete net? Explain.

Answer: No. A net must be connected and fold into the solid without overlapping faces.

Matching face sizes are necessary but not sufficient: a net is a connected planar arrangement that folds into the cuboid.

Question 35 · reasoning

A cuboid has side lengths 5 cm, 7 cm and 4 cm. Find the combined length of all twelve edges. Explain or sketch the mathematical relationship.

Answer: 64 cm

There are four of each dimension. Total = 4×(5+7+4)=64 cm. State which quantities or geometric properties justify the method.

Practice examination solutions

Question 1 · reasoning · 3 points

A 11 cm by 7 cm by 4 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 2 · edges · 2 points

A cuboid has side lengths 2 cm, 7 cm and 7 cm. Find the combined length of all twelve edges.

Answer: 64 cm

There are four of each dimension. Total = 4×(2+7+7)=64 cm.

Scoring (2 points): 1 point for a sound method and 1 point for a correct, labeled answer.

Question 3 · reasoning · 3 points

A 5 cm by 11 cm by 18 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 4 · net · 3 points

A cuboid measures 4 cm by 2 cm by 3 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 4×2 faces, two 4×3 faces, two 2×3 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

4×32×34×32×34×24×2

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 5 · net · 3 points

A cuboid measures 3 cm by 2 cm by 6 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 3×2 faces, two 3×6 faces, two 2×6 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

3×62×63×62×63×23×2

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 6 · edges · 2 points

A cuboid has side lengths 4 cm, 8 cm and 9 cm. Find the combined length of all twelve edges.

Answer: 84 cm

There are four of each dimension. Total = 4×(4+8+9)=84 cm.

Scoring (2 points): 1 point for a sound method and 1 point for a correct, labeled answer.

Question 7 · edges · 2 points

A cuboid has side lengths 2 cm, 5 cm and 7 cm. Find the combined length of all twelve edges.

Answer: 56 cm

There are four of each dimension. Total = 4×(2+5+7)=56 cm.

Scoring (2 points): 1 point for a sound method and 1 point for a correct, labeled answer.

Question 8 · net · 3 points

A cuboid measures 4 cm by 5 cm by 3 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 4×5 faces, two 4×3 faces, two 5×3 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

4×35×34×35×34×54×5

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 9 · edges · 2 points

A cuboid has side lengths 2 cm, 3 cm and 8 cm. Find the combined length of all twelve edges.

Answer: 52 cm

There are four of each dimension. Total = 4×(2+3+8)=52 cm.

Scoring (2 points): 1 point for a sound method and 1 point for a correct, labeled answer.

Question 10 · reasoning · 3 points

A 14 cm by 9 cm by 16 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 11 · net · 3 points

A cuboid measures 4 cm by 5 cm by 2 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 4×5 faces, two 4×2 faces, two 5×2 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

4×25×24×25×24×54×5

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 12 · edges · 2 points

A cuboid has side lengths 4 cm, 3 cm and 5 cm. Find the combined length of all twelve edges.

Answer: 48 cm

There are four of each dimension. Total = 4×(4+3+5)=48 cm.

Scoring (2 points): 1 point for a sound method and 1 point for a correct, labeled answer.

Question 13 · net · 3 points

A cuboid measures 4 cm by 3 cm by 2 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 4×3 faces, two 4×2 faces, two 3×2 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

4×23×24×23×24×34×3

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 14 · edges · 2 points

A cuboid has side lengths 2 cm, 3 cm and 5 cm. Find the combined length of all twelve edges.

Answer: 40 cm

There are four of each dimension. Total = 4×(2+3+5)=40 cm.

Scoring (2 points): 1 point for a sound method and 1 point for a correct, labeled answer.

Question 15 · net · 3 points

A cuboid measures 4 cm by 6 cm by 5 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 4×6 faces, two 4×5 faces, two 6×5 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

4×56×54×56×54×64×6

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 16 · reasoning · 3 points

A 2 cm by 4 cm by 18 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 17 · edges · 2 points

A cuboid has side lengths 3 cm, 4 cm and 4 cm. Find the combined length of all twelve edges.

Answer: 44 cm

There are four of each dimension. Total = 4×(3+4+4)=44 cm.

Scoring (2 points): 1 point for a sound method and 1 point for a correct, labeled answer.

Question 18 · reasoning · 3 points

A cuboid has side lengths 6 cm, 8 cm and 8 cm. Find the combined length of all twelve edges. Explain or sketch the mathematical relationship.

Answer: 88 cm

There are four of each dimension. Total = 4×(6+8+8)=88 cm. State which quantities or geometric properties justify the method.

Scoring (3 points): 1 point for identifying the relevant property; 1 for a correct solution; 1 for reasoning.

Question 19 · reasoning · 3 points

A 10 cm by 14 cm by 7 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 20 · net · 3 points

A cuboid measures 6 cm by 2 cm by 4 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 6×2 faces, two 6×4 faces, two 2×4 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

6×42×46×42×46×26×2

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 21 · edges · 2 points

A cuboid has side lengths 4 cm, 8 cm and 6 cm. Find the combined length of all twelve edges.

Answer: 72 cm

There are four of each dimension. Total = 4×(4+8+6)=72 cm.

Scoring (2 points): 1 point for a sound method and 1 point for a correct, labeled answer.

Question 22 · reasoning · 3 points

A 5 cm by 12 cm by 16 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 23 · reasoning · 3 points

A 5 cm by 3 cm by 14 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 24 · reasoning · 3 points

A 7 cm by 9 cm by 16 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 25 · net · 3 points

A cuboid measures 2 cm by 4 cm by 5 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 2×4 faces, two 2×5 faces, two 4×5 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

2×54×52×54×52×42×4

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 26 · net · 3 points

A cuboid measures 5 cm by 6 cm by 4 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 5×6 faces, two 5×4 faces, two 6×4 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

5×46×45×46×45×65×6

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 27 · net · 3 points

A cuboid measures 5 cm by 4 cm by 2 cm. List the dimensions of its six faces, including repeated face sizes.

Answer: Two 5×4 faces, two 5×2 faces, two 4×2 faces

Opposite faces come in matching pairs, so there are two of each of the three face sizes.

5×24×25×24×25×45×4

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 28 · reasoning · 3 points

A 5 cm by 3 cm by 9 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 29 · construction · 3 points

Draw one connected, foldable six-face net of a 6 cm by 5 cm by 4 cm cuboid. Label each face with its dimensions.

Draw and label a foldable net
Answer: A valid connected six-face net: Two 6×5 faces, two 6×4 faces, two 5×4 faces

One valid arrangement uses a connected strip of four side faces, plus two matching end faces attached without overlap. Other foldable nets are also correct.

6×45×46×45×46×56×5

Scoring (3 points): 1 point for identifying the relevant property; 1 for a correct solution; 1 for reasoning.

Question 30 · reasoning · 3 points

Does a 15-cm long rectangular box have 8 or 12 vertices? Explain.

Answer: 8 vertices

A vertex is a corner; there are four corners on each of two opposite rectangular ends.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 31 · reasoning · 3 points

A 6 cm by 17 cm by 13 cm cuboid has how many faces, edges, and vertices? Explain or sketch the mathematical relationship.

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points. State which quantities or geometric properties justify the method.

Scoring (3 points): 1 point for identifying the relevant property; 1 for a correct solution; 1 for reasoning.

Question 32 · reasoning · 3 points

A 10 cm by 17 cm by 14 cm cuboid has how many faces, edges, and vertices?

Answer: 6 faces, 12 edges, 8 vertices

Count six rectangular faces, twelve meeting segments and eight corner points.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 33 · edges · 2 points

A cuboid has side lengths 7 cm, 5 cm and 6 cm. Find the combined length of all twelve edges.

Answer: 72 cm

There are four of each dimension. Total = 4×(7+5+6)=72 cm.

Scoring (2 points): 1 point for a sound method and 1 point for a correct, labeled answer.

Question 34 · reasoning · 3 points

Does a 7-cm long rectangular box have 8 or 12 vertices? Explain.

Answer: 8 vertices

A vertex is a corner; there are four corners on each of two opposite rectangular ends.

Scoring (3 points): 1 point for identifying the relationship; 1 point for the correct working or figure; 1 point for a justified answer.

Question 35 · construction · 4 points

Draw one connected, foldable six-face net of a 6 cm by 2 cm by 4 cm cuboid. Label each face with its dimensions.

Draw and label a foldable net
Answer: A valid connected six-face net: Two 6×2 faces, two 6×4 faces, two 2×4 faces

One valid arrangement uses a connected strip of four side faces, plus two matching end faces attached without overlap. Other foldable nets are also correct.

6×42×46×42×46×26×2

Scoring (4 points): 1 point for a correctly interpreted diagram or setup; 1 for a valid method; 1 for the result; 1 for clearly labeled construction/dimensions.