Water flows into a tank at the rate of 55 ℓ per minute. After 22 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 1.6 m long, 0.1 m wide and 22 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
= 55 x 22
= 1210 ℓ
2 u = 1210
1 u = 1210 ÷ 2 = 605
Volume of water to fill the tank to the brim
= 5 u - 2 u
= 3 u
= 3 x 605
= 1815 ℓ
(b)
1 m = 100 cm
1.6 m = 160 cm
0.1 m = 10 cm
Volume of each container
= 160 x 10 x 22
= 35200 cm
3 Volume of water in the tank = 1210 ℓ
1 ℓ = 1000 mℓ
1210 ℓ = 1210000 mℓ
Number of containers needed
= 1210000 ÷ 35200
= 34 r 13200
Minimum number of containers needed
= 34 + 1
= 35
Answer(s): (a) 1815 ℓ; (b) 35