The figure shows an empty rectangular container with a capacity of 32 ℓ. The container has a height of 20 cm. Tap K filled the container at a rate of 3.1 ℓ per minute. Tap L drained water from the container at a rate of 1.6 ℓ per minute. Both taps were turned on for 7 minutes and then turned off.
- What is the base area of the container?
- After both taps were turned off, how much more water is needed to fill the container completely? Give your answer in litres.
(a)
1 ℓ = 1000 mℓ
32 ℓ = 32 x 1000 = 32000 mℓ
Base area of the container
=
Volumeheight =
3200020 = 1600 cm
2 (b)
Volume of water that filled the container per minute when both taps were turned on
= 3.1 - 1.6
= 1.5 ℓ
Volume of water that filled the container in 7 minutes when both taps were turned on
= 7 x 1.5
= 10.5 ℓ
Volume of water needed to fill the container
= 32 - 10.5
= 21.5 ℓ
Answer(s): (a) 1600 cm
2; (b) 21.5 ℓ