Work through the levels in order. Type your answer and press Check — open the worked solution if you get stuck. Answers like -6, 3/4 or 0.25 are typed exactly as shown. A ⭐ Bonus Challenge at the end is extra credit — skip it if the rest was hard work.
Level 1 · Warm-up
1 How many grams is 2 kg?
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2 × 1 000 = 2 000 g.
2 Write 1 kg 250 g in grams, and 3 500 g in kilograms.
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1 250 g; 3.5 kg.
3 Four identical blocks balance a 600 g weight. What is the mass of one block, in grams?
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150 g.
Level 2 · Core
4 Three identical apples balance a pear and a 100 g weight. The pear weighs 200 g. What is the mass of one apple?
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3 apples = 300 g, so one apple = 100 g.
5 A + B = 20 kg, B + C = 26 kg, A + C = 30 kg. Give the total mass of all three, and the mass of B.
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76 ÷ 2 = 38. B = 38 − 30 = 8 kg.
6 A truck weighs 2 t 400 kg and carries 1 800 kg of cargo. What is the total mass, in kilograms?
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4 200 kg.
Level 3 · Challenge
7 Three boxes weighed in pairs: A + B = 28 kg, B + C = 32 kg, A + C = 38 kg.1 The three boxes weigh 49 kg altogether.
2 Box A weighs 17 kg.
3 Box C weighs 19 kg.
Which statements are correct?
2 Box A weighs 17 kg.
3 Box C weighs 19 kg.
Which statements are correct?
Show worked solution
98 ÷ 2 = 49 (1 ✓). A = 49 − 32 = 17 (2 ✓). C = 49 − 28 = 21, not 19 (3 ✗). 1 and 2.
8 The same three boxes: A + B = 28, B + C = 32, A + C = 38. Give the mass of the heaviest box and of the lightest.
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C = 49 − 28 = 21 kg is heaviest; B = 49 − 38 = 11 kg is lightest.
9 A bridge limit is 5 t. A truck weighs 2 t 400 kg and carries 1 800 kg of cargo. How many more kilograms of cargo could it carry and still be under the limit?
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5 000 − 4 200 = 800 kg.