An empty rectangular container has a capacity of 114 ℓ and a height of 15 cm. At 7 a.m., Tap F is turned on to fill the container at a rate of 7 ℓ per minute for 20 minutes. After 8 minutes, Tap G is turned on to drain water from the container at a rate of 4 ℓ per minute for 23 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 
7 ℓ = 7000 cm³ 
4 ℓ = 4000 cm³ 
114 ℓ = 114000 cm³

Volume of water flowed in from Tap F
= 20 x 7000
= 140000 cm³

Volume of water from drained from Tap G
= 23 x 4000
= 92000 cm³

Volume of water left in the container
= 140000 - 92000
= 48000 cm³

Base area of the container
= 114000 ÷ 15
= 7600 cm² 

Height of water left in the container
= 48000 ÷ 7600
≈ 6.3 cm

Answer(s): 6.3 cm