A rectangular tank measuring 70 cm by 50 cm by 28 cm was ¹₅ filled with water. Sarah turned on a tap at 4.21 p.m. to fill more water into the tank. She turned off the tap at 4.42 p.m. The tank was ⁵₇ 
filled with water. Given that the water flowed out of the tap at the same rate, find the volume of water that flowed out of the tap in a minute. Give your answer in litres.
Volume of water in the tank at first
= ¹₅ x 70 x 50 x 28
= 19600 cm³

Volume of water in the tank in the end
= ⁵₇ x 70 x 50 x 28
= 70000 cm³

Volume of water added into the tank by the tap
= 70000 - 19600
= 50400 cm³

1000 mℓ = 1 ℓ
50400 mℓ = 50400 ÷ 1000 = 50.4 ℓ

From 4.21 p.m. to 4.42 p.m.: 21 min

Volume of water that flowed out of the tap in a minute
= 50.4 ÷ 21
= 2.4 ℓ 

Answer(s): 2.4 ℓ