Primary 5 Mathematics Measurement Quiz

Primary 5 Mathematics Quiz - Measurement: Answer Key

Total Marks: 40

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Section A: Multiple Choice (1 mark each)

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1. C) tonnes

Explanation: A school bus is very heavy. Grams and kilograms are too small (a bus weighs thousands of kilograms). Tonnes are used for heavy vehicles; 1 tonne = 1000 kg. A typical school bus might weigh 5-10 tonnes. Milligrams are for very light objects like medicine doses.

Common mistake: Choosing kilograms without realising how heavy a bus actually is.

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2. C) 5800 mℓ

Explanation: To convert litres to millilitres, multiply by 1000. $5.8 \times 1000 = 5800 \text{ mℓ}$

Remember: 1 ℓ = 1000 mℓ. The decimal point moves 3 places to the right.

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3. B) 8.5 m

Explanation: To convert centimetres to metres, divide by 100. $850 \div 100 = 8.5 \text{ m}$

Remember: 1 m = 100 cm. The decimal point moves 2 places to the left.

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4. A) 1.85 kg or B) 1.95 kg

Correction: A) 1.85 kg

Explanation: First convert everything to the same unit. 650 g = 0.65 kg. $\text{Rice left} = 2.5 - 0.65 = 1.85 \text{ kg}$

Or convert to grams: 2.5 kg = 2500 g; 2500 - 650 = 1850 g = 1.85 kg.

Common mistake: Forgetting to convert units before subtracting, or arithmetic errors.

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5. D) 3000 cm³

Explanation: Volume of cuboid = length × width × height $V = 20 \times 15 \times 10 = 3000 \text{ cm}^3$

Units are cm × cm × cm = cm³.

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Section B: Short Answer (2 marks each unless stated)

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6. 4250 m

Method: $4.25 \text{ km} = 4.25 \times 1000 \text{ m} = 4250 \text{ m}$

Concept: 1 km = 1000 m. Multiply by 1000 (move decimal 3 places right).

[1 mark for correct method, 1 mark for correct answer]

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7. 250 mℓ

Method: $\text{Each glass} = 1.5 \div 6 = 0.25 \text{ ℓ} = 0.25 \times 1000 = 250 \text{ mℓ}$

Or: 1.5 ℓ = 1500 mℓ; 1500 ÷ 6 = 250 mℓ.

Concept: Division for equal sharing; conversion between ℓ and mℓ.

[1 mark for correct division, 1 mark for unit conversion and final answer]

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8. 5350 g (or 5.35 kg)

Method: $\text{Total mass} = 3.6 + 1.75 = 5.35 \text{ kg} = 5.35 \times 1000 = 5350 \text{ g}$

Concept: Addition with decimals; conversion kg to g (×1000).

[1 mark for correct total in kg, 1 mark for conversion to g]

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9. 14 pieces

Method: $\text{Number of pieces} = 8.4 \div 0.6 = 84 \div 6 = 14$

Or: 8.4 ÷ 0.6 = (8.4 × 10) ÷ (0.6 × 10) = 84 ÷ 6 = 14.

Concept: Division involving decimals; multiply both by 10 to simplify.

[1 mark for method, 1 mark for answer]

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10. 7.5 ℓ

Method: $\text{Volume of water} = 30 \times 20 \times \frac{25}{2} = 30 \times 20 \times 12.5 = 7500 \text{ cm}^3$ $\text{In litres} = 7500 \div 1000 = 7.5 \text{ ℓ}$

Or: Full volume = 30 × 20 × 25 = 15000 cm³ = 15 ℓ; half = 7.5 ℓ.

Concept: Volume of cuboid; halving; cm³ to ℓ conversion (1000 cm³ = 1 ℓ).

[1 mark for correct water volume in cm³, 1 mark for conversion to ℓ]

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11. 126 cm²

Method: $\text{Area of rectangle} = 12 \times 8 = 96 \text{ cm}^2$ $\text{Area of triangle} = \frac{1}{2} \times 12 \times 5 = 30 \text{ cm}^2$ $\text{Total area} = 96 + 30 = 126 \text{ cm}^2$

Concept: Rectangle area = length × width; Triangle area = ½ × base × height. Triangle shares base CD = 12 cm with rectangle's side.

[1 mark for each area calculation, 1 mark for total — but max 2 marks; adjust to 1 mark for rectangle, 1 mark for triangle and total]

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12. 8 cm

Method: $\text{Volume of cuboid} = \text{base area} \times \text{height}$ $480 = 60 \times h$ $h = 480 \div 60 = 8 \text{ cm}$

Concept: Rearranging volume formula. Volume = area of base × height, so height = volume ÷ base area.

[1 mark for correct formula, 1 mark for answer]

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13. 40 km

Method: $\text{Actual distance} = 8 \times 5 = 40 \text{ km}$

Concept: Scale interpretation. Map distance × scale factor = actual distance.

[1 mark for method, 1 mark for answer]

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14. 0.9 kg (or 900 g)

Method: $\text{Flour used} = \frac{3}{8} \times 2.4 = \frac{3 \times 2.4}{8} = \frac{7.2}{8} = 0.9 \text{ kg}$

Or: 2.4 kg = 2400 g; 3/8 × 2400 = 900 g = 0.9 kg.

Concept: Fraction of a quantity. "Of" means multiply.

[1 mark for correct operation set up, 1 mark for answer]

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15. 56 cm²

Method: $\text{Area of trapezium} = \frac{1}{2} \times (a + b) \times h = \frac{1}{2} \times (6 + 10) \times 7 = \frac{1}{2} \times 16 \times 7 = 56 \text{ cm}^2$

Where a and b are the two parallel sides (6 cm and 10 cm), and h = 7 cm is the perpendicular height.

Concept: Trapezium area formula. The height must be perpendicular to the parallel sides.

[1 mark for correct formula with values, 1 mark for correct calculation]

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Section C: Problem Solving

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16. (Total: 5 marks)

(a) 60 000 cm³ — (1 mark)

Method: $V = 40 \times 30 \times 50 = 60000$ cm³

(b) 42 ℓ — (2 marks)

Method: $\text{Volume of water} = 40 \times 30 \times 35 = 42000 \text{ cm}^3$ $\text{In litres} = 42000 \div 1000 = 42 \text{ ℓ}$

[1 mark for volume in cm³, 1 mark for conversion to ℓ]

(c) 84 minutes — (2 marks)

Method: $\text{Time} = 42 \div 0.5 = 84 \text{ minutes}$

Or: 0.5 ℓ/min = 1 ℓ per 2 minutes; 42 × 2 = 84 minutes.

Concept: Rate = volume ÷ time, so time = volume ÷ rate.

[1 mark for correct formula/relationship, 1 mark for answer]

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17. (Total: 4 marks)

(a) 0.3 kg — (1 mark)

Method: $2 \times 150 = 300$ g = $300 \div 1000 = 0.3$ kg

(b) 0.5 kg — (3 marks)

Method: $\text{Total mass of books} = 1.8 - 0.3 = 1.5 \text{ kg}$ $\text{Mass of one book} = 1.5 \div 3 = 0.5 \text{ kg}$

Mark breakdown:

• [1 mark] Subtract folders' mass from total
• [1 mark] Divide by 3 for one book
• [1 mark] Correct final answer with unit

Common mistake: Forgetting to convert grams to kilograms in part (a), leading to wrong subtraction.

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18. (Total: 4 marks)

(a) 750 mℓ — (2 marks)

Method: $1.2 \text{ ℓ} = 1200 \text{ mℓ}$ $\text{Water added} = 1200 - 450 = 750 \text{ mℓ}$

[1 mark for conversion, 1 mark for subtraction]

(b) 0.24 ℓ — (2 marks)

Method: $\text{Each beaker} = 1200 \div 5 = 240 \text{ mℓ} = 240 \div 1000 = 0.24 \text{ ℓ}$

Or: 1.2 ℓ ÷ 5 = 0.24 ℓ directly.

[1 mark for division, 1 mark for correct unit conversion/final answer]

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19. (Total: 4 marks)

(a) 36 m² — (2 marks)

Method: $\text{Living room area} = 6 \times 4 = 24 \text{ m}^2$ $\text{Dining area} = 3 \times 4 = 12 \text{ m}^2$ $\text{Total} = 24 + 12 = 36 \text{ m}^2$

Or: Combined length = 6 + 3 = 9 m (if arranged appropriately), area = 9 × 4 = 36 m².

Image interpretation: Based on placeholder description—Living Room 6m × 4m, Dining Area 3m × 4m sharing the 4m width typical of L-shape or linear arrangement.

[1 mark for individual areas, 1 mark for total]

(b) 144 tiles — (2 marks)

Method: $\text{Tile side} = 50 \text{ cm} = 0.5 \text{ m}$ $\text{Area of one tile} = 0.5 \times 0.5 = 0.25 \text{ m}^2$ $\text{Number of tiles} = 36 \div 0.25 = 144$

Or in cm: Room = 36 m² = 360000 cm²; Tile = 50 × 50 = 2500 cm²; 360000 ÷ 2500 = 144.

[1 mark for tile area calculation, 1 mark for correct division]

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20. (Total: 5 marks)

(a) 8000 cm³ — (1 mark)

Method: $V = 20 \times 20 \times 20 = 8000$ cm³

(b) 6 ℓ — (2 marks)

Method: $\text{Volume of water} = \frac{3}{4} \times 8000 = 6000 \text{ cm}^3 = 6000 \div 1000 = 6 \text{ ℓ}$

[1 mark for fraction multiplication, 1 mark for cm³ to ℓ conversion]

(c) 3/16 — (2 marks)

Method: $1.5 \text{ ℓ} = 1500 \text{ mℓ} = 1500 \text{ cm}^3$ $\text{Fraction filled} = \frac{1500}{8000} = \frac{15}{80} = \frac{3}{16}$

[1 mark for correct conversion and fraction set up, 1 mark for simplified answer]

Common mistake: Using 1.5 ℓ = 1500 directly with 8000 without converting to same units (though answer is same here, method is unsound). Or leaving as 15/80 unsimplified.

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End of Answer Key