Water flows into a tank at the rate of 45 ℓ per minute. After 25 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 1.1 m long, 0.3 m wide and 25 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
= 45 x 25
= 1125 ℓ
3 u = 1125
1 u = 1125 ÷ 3 = 375
Volume of water to fill the tank to the brim
= 5 u - 3 u
= 2 u
= 2 x 375
= 750 ℓ
(b)
1 m = 100 cm
1.1 m = 110 cm
0.3 m = 30 cm
Volume of each container
= 110 x 30 x 25
= 82500 cm
3 Volume of water in the tank = 1125 ℓ
1 ℓ = 1000 mℓ
1125 ℓ = 1125000 mℓ
Number of containers needed
= 1125000 ÷ 82500
= 13 r 52500
Minimum number of containers needed
= 13 + 1
= 14
Answer(s): (a) 750 ℓ; (b) 14