GK 2015 Q10
10. During a rainstorm, 15 litres of water fell per square metre. By how much did the water level in Michael's outdoor pool rise?
- A 150 cm
- B 0.15 cm
- C 15 cm
- D 1.5 cm
- E It depends upon the size of the pool
Grey Kangaroo 2015, Question 10. © UK Mathematics Trust. Original paper on ukmt.org.uk
Answer: D 1.5 cm
One litre is equivalent to 1000 cm3. Hence 15 litres falling over an area of one square metre is equivalent to 15 000 cm3 falling over an area of 10 000 cm2. Therefore the amount the water in Michael's pool would rise by, in cm, is 15 000 ÷ 10 000 = 1.5.
Solution © UK Mathematics Trust, from the GK 2015 solutions.