An empty rectangular container has a capacity of 195 ℓ and a height of 100 cm. At 7 a.m., Tap Z is turned on to fill the container at a rate of 4 ℓ per minute for 15 minutes. After 15 minutes, Tap A is turned on to drain water from the container at a rate of 5 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 
4 ℓ = 4000 cm³ 
5 ℓ = 5000 cm³ 
195 ℓ = 195000 cm³

Volume of water flowed in from Tap Z
= 15 x 4000
= 60000 cm³

Volume of water from drained from Tap A
= 7 x 5000
= 35000 cm³

Volume of water left in the container
= 60000 - 35000
= 25000 cm³

Base area of the container
= 195000 ÷ 100
= 1950 cm² 

Height of water left in the container
= 25000 ÷ 1950
≈ 12.8 cm

Answer(s): 12.8 cm