An empty rectangular container has a capacity of 154 ℓ and a height of 35 cm. At 10 a.m., Tap C is turned on to fill the container at a rate of 6 ℓ per minute for 18 minutes. After 10 minutes, Tap D is turned on to drain water from the container at a rate of 2 ℓ per minute for 23 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 
6 ℓ = 6000 cm³ 
2 ℓ = 2000 cm³ 
154 ℓ = 154000 cm³

Volume of water flowed in from Tap C
= 18 x 6000
= 108000 cm³

Volume of water from drained from Tap D
= 23 x 2000
= 46000 cm³

Volume of water left in the container
= 108000 - 46000
= 62000 cm³

Base area of the container
= 154000 ÷ 35
= 4400 cm² 

Height of water left in the container
= 62000 ÷ 4400
≈ 14.1 cm

Answer(s): 14.1 cm