³₄ of a rectangular tank, 68 cm by 32 cm by 20 cm, is filled with water. A cubical container of edge 27 cm is filled with water to a depth of 13 cm. If the water in the rectangular tank is transferred to the cubical container until it is filled to its brim, how many litres of water will be left in the rectangular tank?
Volume of water in the tank 
= ³₄ x 68 x 32 x 20
= 32640 cm³ 

Height increase of the cubical container in order to be filled to the brim
= 27 - 13
= 14 cm

Volume of water needed to be filled in the cubical container
= 27 x 27 x 14
= 10206 cm³ 

Volume of water left in the rectangular tank 
= 32640 - 10206
= 22434 cm³ 

1000 cm³ = 1 ℓ

22434 cm³ = 22434 ÷ 1000 = 22.434 ℓ

Answer(s): 22.434 ℓ