Water flows into a tank through Tap S and flows out of the container through Tap T. The capacity of a tank is 66 litres. When only Tap S is turned on, the container is completely filled in 12 minutes. When only Tap T 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 66% of the tank?
- How much water has flowed out through Tap T by the time the tank is 35 filled with water? Express your answer in litres.
(a)
Tap S :
12 min → 1 tank
1 min →
112 tank
13 hour =
13 x 60 = 20 min
Tap T:
20 min → 1 tank
1 min →
120 tank
Tap S and Tap T:
1 min →
112 -
120 =
560 -
360 =
130 tank
1 tank →
301 = 30 min
66% tank → 66% x 30 = 19.8 min
(b)
Time taken to fill
35 of the tank
1 tank → 30 min
35 tank → 30 x
35 = 18 min
Volume that flows out per min
=
120 tank
=
120 x 66
= 3.3 ℓ
Volume of water that flowed out through Tap T in 18 min
= 18 x 3.3
= 59.4 ℓ
Answer(s): (a) 19.8 min; (b) 59.4 ℓ