Water flows into a tank at the rate of 30 ℓ per minute. After 14 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, 0.1 m wide and 14 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
= 30 x 14
= 420 ℓ
2 u = 420
1 u = 420 ÷ 2 = 210
Volume of water to fill the tank to the brim
= 5 u - 2 u
= 3 u
= 3 x 210
= 630 ℓ
(b)
1 m = 100 cm
1.9 m = 190 cm
0.1 m = 10 cm
Volume of each container
= 190 x 10 x 14
= 26600 cm
3 Volume of water in the tank = 420 ℓ
1 ℓ = 1000 mℓ
420 ℓ = 420000 mℓ
Number of containers needed
= 420000 ÷ 26600
= 15 r 21000
Minimum number of containers needed
= 15 + 1
= 16
Answer(s): (a) 630 ℓ; (b) 16