Water flows into a tank at the rate of 35 ℓ per minute. After 16 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 1.4 m long, 0.5 m wide and 16 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
= 35 x 16
= 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
1.4 m = 140 cm
0.5 m = 50 cm
Volume of each container
= 140 x 50 x 16
= 112000 cm
3 Volume of water in the tank = 560 ℓ
1 ℓ = 1000 mℓ
560 ℓ = 560000 mℓ
Number of containers needed
= 560000 ÷ 112000
= 5 r 0
Minimum number of containers needed
= 5 + 1
= 6
Answer(s): (a) 140 ℓ; (b) 6