At a community centre, Pool M and Pool N are rectangular paddling pools.
- Pool M measures 2 m long, 3 m wide and 1 m deep. It is 34 full of water. Find the volume of water in Pool M.
- Pool N is 25 full of water. Once the water in Pool M is emptied into Pool N, Pool N is 35 full of water. The height of Pool N is 112 m. Find the area of the base of Pool N.
Need a hint?
Compare Pool N's fullness before and after the water is added. That difference represents the transferred water as a fraction of Pool N's full capacity.
Worked answer
- Full volume of Pool M = 2 × 3 × 1 = 6 m³.
- Water volume in Pool M = 6 × 34 = 412 m³.
- Increase in Pool N's fullness = 35 − 25 = 15.
- Full capacity of Pool N = 412 ÷ 15 = 2212 m³.
- Base area of Pool N = 2212 ÷ 112 = 15 m².
Answer: 15 m²
The mistake this question tests
Habit
Calculation slip
The transferred water is only the extra 15 of Pool N's capacity, not its entire initial or final amount. A common error is to use 25 or 35 instead of the difference.
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