An empty rectangular tank has a capacity of 32 ℓ and a height of 40 cm. At 8 a.m., Tap M is turned on to fill the tank at a rate of 6 ℓ per minute for 17 minutes. After 13 minutes, Tap N is turned on to drain water from the tank at a rate of 8 ℓ per minute for 9 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 
8 ℓ = 8000 cm³ 
32 ℓ = 32000 cm³

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

Volume of water from drained from Tap N
= 9 x 8000
= 72000 cm³

Volume of water left in the tank
= 102000 - 72000
= 30000 cm³

Base area of the tank
= 32000 ÷ 40
= 800 cm² 

Height of water left in the tank
= 30000 ÷ 800
≈ 37.5 cm

Answer(s): 37.5 cm