An empty rectangular container has a capacity of 172 ℓ and a height of 20 cm. At 7 a.m., Tap Z is turned on to fill the container at a rate of 4 ℓ per minute for 19 minutes. After 11 minutes, Tap A is turned on to drain water from the container at a rate of 5 ℓ per minute for 12 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 
4 ℓ = 4000 cm³ 
5 ℓ = 5000 cm³ 
172 ℓ = 172000 cm³

Volume of water flowed in from Tap Z
= 19 x 4000
= 76000 cm³

Volume of water from drained from Tap A
= 12 x 5000
= 60000 cm³

Volume of water left in the container
= 76000 - 60000
= 16000 cm³

Base area of the container
= 172000 ÷ 20
= 8600 cm² 

Height of water left in the container
= 16000 ÷ 8600
≈ 1.9 cm

Answer(s): 1.9 cm