3 identical 9-cm cubes are placed in an empty rectangular tank of length 89 cm and width 28 cm. The tank is then filled with water from a tap flowing at a rate of 10 litres per minute. It takes 14 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
= 9 x 9 x 9
= 729 cm³ 

Volume of 3 cubes
= 3 x 729
= 2187 cm³ 

1 ℓ = 1000 mℓ
10 ℓ = 10000 mℓ

Volume of water in the tank
= 14 x 10000
= 140000 mℓ

Volume of ¹₂ of the tank
= 140000 + 2187
= 142187 mℓ

Volume of the tank
= 142187 ÷ ¹₂
= 142187 x ²₁
= 284374 mℓ

Base area
= 89 x 28
= 2492 cm² 

Height of the tank
= 284374 ÷ 2492
≈ 114.1 cm

Answer(s): 114.1 cm