An empty rectangular tank has a capacity of 153 ℓ and a height of 50 cm. At 6 a.m., Tap Z is turned on to fill the tank at a rate of 6 ℓ per minute for 17 minutes. After 3 minutes, Tap A is turned on to drain water from the tank at a rate of 4 ℓ per minute for 14 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 
6 ℓ = 6000 cm³ 
4 ℓ = 4000 cm³ 
153 ℓ = 153000 cm³

Volume of water flowed in from Tap Z
= 17 x 6000
= 102000 cm³

Volume of water from drained from Tap A
= 14 x 4000
= 56000 cm³

Volume of water left in the tank
= 102000 - 56000
= 46000 cm³

Base area of the tank
= 153000 ÷ 50
= 3060 cm² 

Height of water left in the tank
= 46000 ÷ 3060
≈ 15 cm

Answer(s): 15 cm