Educational worksheet for calculating the volume of cubes and cuboids, featuring six shapes with given dimensions.

Explanation:
To find the volume of a cuboid (which includes cubes — a cube is just a special cuboid where all sides are equal), we use the formula:

Volume = length × width × height

All measurements must be in the same unit (here, centimetres), and the answer will be in cm³.

Let’s go through each shape one by one:

1. Dimensions: 6 cm (length) × 5.5 cm (width) × 7 cm (height)
Volume = 6 × 5.5 × 7
First, 6 × 5.5 = 33
Then, 33 × 7 = 231 cm³

2. Dimensions: 9 cm × 12 cm × 8 cm
Volume = 9 × 12 × 8
9 × 12 = 108
108 × 8 = 864 cm³

3. Dimensions: 9 cm × 8.5 cm × 11 cm
Volume = 9 × 8.5 × 11
9 × 8.5 = 76.5
76.5 × 11 =
→ 76.5 × 10 = 765
→ 76.5 × 1 = 76.5
Total = 765 + 76.5 = 841.5 cm³

4. Dimensions: 13 cm × 8 cm × 7 cm
Volume = 13 × 8 × 7
13 × 8 = 104
104 × 7 =
→ 100 × 7 = 700
→ 4 × 7 = 28
Total = 700 + 28 = 728 cm³

5. Dimensions: 9 cm × 11 cm × 15 cm
Volume = 9 × 11 × 15
9 × 11 = 99
99 × 15 =
→ 100 × 15 = 1500
→ subtract 1 × 15 = 15
So 1500 − 15 = 1485 cm³

6. Dimensions: 21 cm × 7 cm × 11.5 cm
Volume = 21 × 7 × 11.5
First, 21 × 7 = 147
Then, 147 × 11.5
Break it down:
147 × 11 = 147 × (10 + 1) = 1470 + 147 = 1617
147 × 0.5 = 73.5
Add: 1617 + 73.5 = 1690.5 cm³

Let me double-check each multiplication to avoid mistakes:

1. 6 × 5.5 = 33 ✔️; 33 × 7 = 231 ✔️
2. 9 × 12 = 108 ✔️; 108 × 8 = 864 ✔️
3. 9 × 8.5 = 76.5 ✔️; 76.5 × 11 = 841.5 ✔️
4. 13 × 8 = 104 ✔️; 104 × 7 = 728 ✔️
5. 9 × 11 = 99 ✔️; 99 × 15 = 1485 ✔️
6. 21 × 7 = 147 ✔️; 147 × 11.5 = 147 × (11 + 0.5) = 1617 + 73.5 = 1690.5 ✔️

All correct.

Final Answer:
1. 231 cm³
2. 864 cm³
3. 841.5 cm³
4. 728 cm³
5. 1485 cm³
6. 1690.5 cm³