Water flows into a container through Tap C and flows out of the container through Tap D. The capacity of a container is 44 litres. When only Tap C is turned on, the container is completely filled in 16 minutes. When only Tap D is turned on, it takes
13 hour for all the water to flow out. If both taps are turned on at the same time,
- How long does it take to fill 50% of the container?
- How much water has flowed out through Tap D by the time the container is 25 filled with water? Express your answer in litres.
(a)
Tap C :
16 min → 1 container
1 min →
116 container
13 hour =
13 x 60 = 20 min
Tap D:
20 min → 1 container
1 min →
120 container
Tap C and Tap D:
1 min →
116 -
120 =
580 -
480 =
180 container
1 container →
801 = 80 min
50% container → 50% x 80 = 40 min
(b)
Time taken to fill
25 of the container
1 container → 80 min
25 container → 80 x
25 = 32 min
Volume that flows out per min
=
120 container
=
120 x 44
= 2.2 ℓ
Volume of water that flowed out through Tap D in 32 min
= 32 x 2.2
= 70.4 ℓ
Answer(s): (a) 40 min; (b) 70.4 ℓ