Water flows into a tank at the rate of 30 ℓ per minute. After 19 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 1.4 m long, 0.4 m wide and 19 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
= 30 x 19
= 570 ℓ
3 u = 570
1 u = 570 ÷ 3 = 190
Volume of water to fill the tank to the brim
= 5 u - 3 u
= 2 u
= 2 x 190
= 380 ℓ
(b)
1 m = 100 cm
1.4 m = 140 cm
0.4 m = 40 cm
Volume of each container
= 140 x 40 x 19
= 106400 cm
3 Volume of water in the tank = 570 ℓ
1 ℓ = 1000 mℓ
570 ℓ = 570000 mℓ
Number of containers needed
= 570000 ÷ 106400
= 5 r 38000
Minimum number of containers needed
= 5 + 1
= 6
Answer(s): (a) 380 ℓ; (b) 6