Water flows into a tank through Tap B and flows out of the container through Tap C. The capacity of a tank is 78 litres. When only Tap B is turned on, the container is completely filled in 16 minutes. When only Tap C 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 52% of the tank?
- How much water has flowed out through Tap C by the time the tank is 35 filled with water? Express your answer in litres.
(a)
Tap B :
16 min → 1 tank
1 min →
116 tank
13 hour =
13 x 60 = 20 min
Tap C:
20 min → 1 tank
1 min →
120 tank
Tap B and Tap C:
1 min →
116 -
120 =
580 -
480 =
180 tank
1 tank →
801 = 80 min
52% tank → 52% x 80 = 41.6 min
(b)
Time taken to fill
35 of the tank
1 tank → 80 min
35 tank → 80 x
35 = 48 min
Volume that flows out per min
=
120 tank
=
120 x 78
= 3.9 ℓ
Volume of water that flowed out through Tap C in 48 min
= 48 x 3.9
= 187.2 ℓ
Answer(s): (a) 41.6 min; (b) 187.2 ℓ