Water flows into a tank at the rate of 40 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 1.3 m long, 0.1 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
= 40 x 14
= 560 ℓ
4 u = 560
1 u = 560 ÷ 4 = 140
Volume of water to fill the tank to the brim
= 5 u - 4 u
= 1 u
= 1 x 140
= 140 ℓ
(b)
1 m = 100 cm
1.3 m = 130 cm
0.1 m = 10 cm
Volume of each container
= 130 x 10 x 14
= 18200 cm
3 Volume of water in the tank = 560 ℓ
1 ℓ = 1000 mℓ
560 ℓ = 560000 mℓ
Number of containers needed
= 560000 ÷ 18200
= 30 r 14000
Minimum number of containers needed
= 30 + 1
= 31
Answer(s): (a) 140 ℓ; (b) 31