Water flows into a tank at the rate of 40 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 1.3 m long, 0.3 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
= 40 x 16
= 640 ℓ
4 u = 640
1 u = 640 ÷ 4 = 160
Volume of water to fill the tank to the brim
= 5 u - 4 u
= 1 u
= 1 x 160
= 160 ℓ
(b)
1 m = 100 cm
1.3 m = 130 cm
0.3 m = 30 cm
Volume of each container
= 130 x 30 x 16
= 62400 cm
3 Volume of water in the tank = 640 ℓ
1 ℓ = 1000 mℓ
640 ℓ = 640000 mℓ
Number of containers needed
= 640000 ÷ 62400
= 10 r 16000
Minimum number of containers needed
= 10 + 1
= 11
Answer(s): (a) 160 ℓ; (b) 11