Water flows into a tank through Tap H and flows out of the container through Tap J. The capacity of a tank is 66 litres. When only Tap H is turned on, the container is completely filled in 16 minutes. When only Tap J 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 80% of the tank?
- How much water has flowed out through Tap J by the time the tank is 45 filled with water? Express your answer in litres.
(a)
Tap H :
16 min → 1 tank
1 min →
116 tank
13 hour =
13 x 60 = 20 min
Tap J:
20 min → 1 tank
1 min →
120 tank
Tap H and Tap J:
1 min →
116 -
120 =
580 -
480 =
180 tank
1 tank →
801 = 80 min
80% tank → 80% x 80 = 64 min
(b)
Time taken to fill
45 of the tank
1 tank → 80 min
45 tank → 80 x
45 = 64 min
Volume that flows out per min
=
120 tank
=
120 x 66
= 3.3 ℓ
Volume of water that flowed out through Tap J in 64 min
= 64 x 3.3
= 211.2 ℓ
Answer(s): (a) 64 min; (b) 211.2 ℓ