An empty rectangular container has a capacity of 156 ℓ and a height of 39 cm. At 9 a.m., Tap X is turned on to fill the container at a rate of 6 ℓ per minute for 19 minutes. After 14 minutes, Tap Y is turned on to drain water from the container at a rate of 2 ℓ per minute for 30 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 
156 ℓ = 156000 cm³

Volume of water flowed in from Tap X
= 19 x 6000
= 114000 cm³

Volume of water from drained from Tap Y
= 30 x 2000
= 60000 cm³

Volume of water left in the container
= 114000 - 60000
= 54000 cm³

Base area of the container
= 156000 ÷ 39
= 4000 cm² 

Height of water left in the container
= 54000 ÷ 4000
≈ 13.5 cm

Answer(s): 13.5 cm