4 identical 8-cm cubes are placed in an empty rectangular tank of length 72 cm and width 30 cm. The tank is then filled with water from a tap flowing at a rate of 9 litres per minute. It takes 10 minutes to fill up ¹₂ of the tank. What is the height of the tank? Correct your answer to 1 decimal place.
Volume of 1 cube
= 8 x 8 x 8
= 512 cm³ 

Volume of 4 cubes
= 4 x 512
= 2048 cm³ 

1 ℓ = 1000 mℓ
9 ℓ = 9000 mℓ

Volume of water in the tank
= 10 x 9000
= 90000 mℓ

Volume of ¹₂ of the tank
= 90000 + 2048
= 92048 mℓ

Volume of the tank
= 92048 ÷ ¹₂
= 92048 x ²₁
= 184096 mℓ

Base area
= 72 x 30
= 2160 cm² 

Height of the tank
= 184096 ÷ 2160
≈ 85.2 cm

Answer(s): 85.2 cm