3 identical 3-cm cubes are placed in an empty rectangular container of length 87 cm and width 21 cm. The container is then filled with water from a tap flowing at a rate of 7 litres per minute. It takes 10 minutes to fill up ¹₂ of the container. What is the height of the container? Correct your answer to 1 decimal place.
Volume of 1 cube
= 3 x 3 x 3
= 27 cm³ 

Volume of 3 cubes
= 3 x 27
= 81 cm³ 

1 ℓ = 1000 mℓ
7 ℓ = 7000 mℓ

Volume of water in the container
= 10 x 7000
= 70000 mℓ

Volume of ¹₂ of the container
= 70000 + 81
= 70081 mℓ

Volume of the container
= 70081 ÷ ¹₂
= 70081 x ²₁
= 140162 mℓ

Base area
= 87 x 21
= 1827 cm² 

Height of the container
= 140162 ÷ 1827
≈ 76.7 cm

Answer(s): 76.7 cm