A carton with 8 identical tins of milk powder weighs 6.34 kg. After Priya took out 3 tins, the carton with the remaining tins weighs 4.15 kg.
- Find the mass of 1 tin in kg.
- Find the mass of the empty carton in grams.
Need a hint?
What does the drop in mass from 6.34 kg to 4.15 kg tell you about the 3 tins Priya took out?
Worked answer
- 3 tins = 6.34 - 4.15 = 2.19 kg
- 1 tin = 2.19 ÷ 3 = 0.73 kg
- 8 tins = 0.73 × 8 = 5.84 kg
- Empty carton = 6.34 - 5.84 = 0.50 kg
- 0.50 kg = 0.50 × 1000 = 500 g
Answer: 500 g
The mistake this question tests
Habit
Converting units (kg, ℓ, m, cm³)
Many pupils divide 6.34 by 8 and treat that as the mass of one tin. That ignores the carton, which is part of the 6.34 kg too.
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