Water flows into a tank at the rate of 60 ℓ per minute. After 23 min, the tap is turned off and the tank is 0.4 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 1.9 m long, 0.5 m wide and 23 cm high. What is the minimum number of containers needed?
(a)
0.4 =
25 Let 5 u be the total volume of water when the tank is completely filled.
Volume of water in the tank
= 60 x 23
= 1380 ℓ
2 u = 1380
1 u = 1380 ÷ 2 = 690
Volume of water to fill the tank to the brim
= 5 u - 2 u
= 3 u
= 3 x 690
= 2070 ℓ
(b)
1 m = 100 cm
1.9 m = 190 cm
0.5 m = 50 cm
Volume of each container
= 190 x 50 x 23
= 218500 cm
3 Volume of water in the tank = 1380 ℓ
1 ℓ = 1000 mℓ
1380 ℓ = 1380000 mℓ
Number of containers needed
= 1380000 ÷ 218500
= 6 r 69000
Minimum number of containers needed
= 6 + 1
= 7
Answer(s): (a) 2070 ℓ; (b) 7