An empty rectangular container has a capacity of 175 ℓ and a height of 28 cm. At 6 a.m., Tap P is turned on to fill the container at a rate of 9 ℓ per minute for 16 minutes. After 12 minutes, Tap Q is turned on to drain water from the container at a rate of 2 ℓ per minute for 29 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 
9 ℓ = 9000 cm³ 
2 ℓ = 2000 cm³ 
175 ℓ = 175000 cm³

Volume of water flowed in from Tap P
= 16 x 9000
= 144000 cm³

Volume of water from drained from Tap Q
= 29 x 2000
= 58000 cm³

Volume of water left in the container
= 144000 - 58000
= 86000 cm³

Base area of the container
= 175000 ÷ 28
= 6250 cm² 

Height of water left in the container
= 86000 ÷ 6250
≈ 13.8 cm

Answer(s): 13.8 cm