Water flows into a tank at the rate of 45 ℓ per minute. After 24 min, the tap is turned off and the tank is 0.6 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 1.5 m long, 0.4 m wide and 24 cm high. What is the minimum number of containers needed?
(a)
0.6 =
35 Let 5 u be the total volume of water when the tank is completely filled.
Volume of water in the tank
= 45 x 24
= 1080 ℓ
3 u = 1080
1 u = 1080 ÷ 3 = 360
Volume of water to fill the tank to the brim
= 5 u - 3 u
= 2 u
= 2 x 360
= 720 ℓ
(b)
1 m = 100 cm
1.5 m = 150 cm
0.4 m = 40 cm
Volume of each container
= 150 x 40 x 24
= 144000 cm
3 Volume of water in the tank = 1080 ℓ
1 ℓ = 1000 mℓ
1080 ℓ = 1080000 mℓ
Number of containers needed
= 1080000 ÷ 144000
= 7 r 72000
Minimum number of containers needed
= 7 + 1
= 8
Answer(s): (a) 720 ℓ; (b) 8