An empty rectangular container has a capacity of 129 ℓ and a height of 60 cm. At 8 a.m., Tap W is turned on to fill the container at a rate of 8 ℓ per minute for 15 minutes. After 12 minutes, Tap X is turned on to drain water from the container at a rate of 3 ℓ per minute for 6 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 
8 ℓ = 8000 cm³ 
3 ℓ = 3000 cm³ 
129 ℓ = 129000 cm³

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

Volume of water from drained from Tap X
= 6 x 3000
= 18000 cm³

Volume of water left in the container
= 120000 - 18000
= 102000 cm³

Base area of the container
= 129000 ÷ 60
= 2150 cm² 

Height of water left in the container
= 102000 ÷ 2150
≈ 47.4 cm

Answer(s): 47.4 cm