A pool measuring 30 m x 28 m x 2 m was completely filled with water. The water was draining out of the tank at a constant rate and became completely empty after 20 minutes.
- What fraction of the pool was filled with water at the end of 17 minutes? Express your answer in the simplest form.
- How many litres of water was drained out of the pool at the end of 9 minutes?
(a)
Fraction of the pool empty per minute =
120 Fraction of the pool empty at 17
th minute
=
120 x 17
=
1720 Fraction of the pool still filled with water
= 1 -
1720 =
2020 -
1720 =
320 (b)
Volume of the pool
= 30 x 28 x 2
= 1680 m
3 = 1680 ℓ
Volume of water drained per minute
= 1680 ÷ 20
= 84 ℓ/min
Volume of the pool drained after the end of 9 minutes
= 9 x 84
= 756 ℓ
Answer(s): (a)
320; (b) 756 ℓ