Aisha and Ben each bought the same total number of cans of soup and packets of noodles. Aisha bought some cans and 30 packets. The total mass of Aisha's cans and packets is 8.43 kg. Ben bought some cans and 18 packets. The total mass of Ben's cans and packets is 10.35 kg. Each packet of noodles has a mass of 85 g.
- How many more cans of soup than Aisha did Ben buy?
- Find the mass of each can of soup. Give your answer in grams.
Need a hint?
Ben has some extra cans in place of the packets Aisha has. Compare 12 cans with 12 packets.
Worked answer
- (a) Aisha has 30 packets and Ben has 18 packets, so Aisha has 30 − 18 = 12 more packets.
- Both have the same total number of items, so Ben has 12 more cans than Aisha.
- (b) Difference in total mass = 10.35 − 8.43 = 1.92 kg, which is 1920 g.
- Ben has 12 more cans but 12 fewer packets, so 12 cans weigh 1920 g more than 12 packets.
- One can is heavier than one packet by 1920 ÷ 12 = 160 g.
- Mass of one can = 85 + 160 = 245 g.
Answer: 245 g
The mistake this question tests
Habit
Converting units (kg, ℓ, m, cm³)
Many pupils stop at 160 g, which is only how much heavier a can is than a packet. Others divide 1.92 by 12 and forget to change kg to g.
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