Water flows into a tank at the rate of 60 ℓ per minute. After 14 min, the tap is turned off and the tank is 0.8 filled with water.
- How much more water is needed to fill it to the brim?
- The water in the tank is then poured into containers each 1.8 m long, 0.2 m wide and 14 cm high. What is the minimum number of containers needed?
(a)
0.8 =
45 Let 5 u be the total volume of water when the tank is completely filled.
Volume of water in the tank
= 60 x 14
= 840 ℓ
4 u = 840
1 u = 840 ÷ 4 = 210
Volume of water to fill the tank to the brim
= 5 u - 4 u
= 1 u
= 1 x 210
= 210 ℓ
(b)
1 m = 100 cm
1.8 m = 180 cm
0.2 m = 20 cm
Volume of each container
= 180 x 20 x 14
= 50400 cm
3 Volume of water in the tank = 840 ℓ
1 ℓ = 1000 mℓ
840 ℓ = 840000 mℓ
Number of containers needed
= 840000 ÷ 50400
= 16 r 33600
Minimum number of containers needed
= 16 + 1
= 17
Answer(s): (a) 210 ℓ; (b) 17