An empty rectangular tank has a capacity of 36 ℓ and a height of 12 cm. At 8 a.m., Tap K is turned on to fill the tank at a rate of 8 ℓ per minute for 15 minutes. After 11 minutes, Tap L is turned on to drain water from the tank at a rate of 10 ℓ per minute for 5 minutes. What is the height of the water level in the tank in the end? Give the answer in 1 decimal place.
1 ℓ = 1000 cm³ 
8 ℓ = 8000 cm³ 
10 ℓ = 10000 cm³ 
36 ℓ = 36000 cm³

Volume of water flowed in from Tap K
= 15 x 8000
= 120000 cm³

Volume of water from drained from Tap L
= 5 x 10000
= 50000 cm³

Volume of water left in the tank
= 120000 - 50000
= 70000 cm³

Base area of the tank
= 36000 ÷ 12
= 3000 cm² 

Height of water left in the tank
= 70000 ÷ 3000
≈ 23.3 cm

Answer(s): 23.3 cm