An empty rectangular container has a capacity of 142 ℓ and a height of 80 cm. At 7 a.m., Tap V is turned on to fill the container at a rate of 3 ℓ per minute for 19 minutes. After 10 minutes, Tap W is turned on to drain water from the container at a rate of 3 ℓ per minute for 7 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 
142 ℓ = 142000 cm³

Volume of water flowed in from Tap V
= 19 x 3000
= 57000 cm³

Volume of water from drained from Tap W
= 7 x 3000
= 21000 cm³

Volume of water left in the container
= 57000 - 21000
= 36000 cm³

Base area of the container
= 142000 ÷ 80
= 1775 cm² 

Height of water left in the container
= 36000 ÷ 1775
≈ 20.3 cm

Answer(s): 20.3 cm