An empty rectangular container has a capacity of 144 ℓ and a height of 10 cm. At 10 a.m., Tap F is turned on to fill the container at a rate of 3 ℓ per minute for 15 minutes. After 9 minutes, Tap G is turned on to drain water from the container at a rate of 3 ℓ per minute for 6 minutes. What is the height of the water level in the container in the end? Give the answer in 1 decimal place.
1 ℓ = 1000 cm³ 
3 ℓ = 3000 cm³ 
3 ℓ = 3000 cm³ 
144 ℓ = 144000 cm³

Volume of water flowed in from Tap F
= 15 x 3000
= 45000 cm³

Volume of water from drained from Tap G
= 6 x 3000
= 18000 cm³

Volume of water left in the container
= 45000 - 18000
= 27000 cm³

Base area of the container
= 144000 ÷ 10
= 14400 cm² 

Height of water left in the container
= 27000 ÷ 14400
≈ 1.9 cm

Answer(s): 1.9 cm