An empty rectangular container has a capacity of 115 ℓ and a height of 10 cm. At 6 a.m., Tap D is turned on to fill the container at a rate of 10 ℓ per minute for 19 minutes. After 10 minutes, Tap E is turned on to drain water from the container at a rate of 5 ℓ per minute for 9 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 
10 ℓ = 10000 cm³ 
5 ℓ = 5000 cm³ 
115 ℓ = 115000 cm³

Volume of water flowed in from Tap D
= 19 x 10000
= 190000 cm³

Volume of water from drained from Tap E
= 9 x 5000
= 45000 cm³

Volume of water left in the container
= 190000 - 45000
= 145000 cm³

Base area of the container
= 115000 ÷ 10
= 11500 cm² 

Height of water left in the container
= 145000 ÷ 11500
≈ 12.6 cm

Answer(s): 12.6 cm