A rectangular container measuring 86 cm by 60 cm by 36 cm was to be filled with water by two taps, F and G. Tap F which fills the tank at a rate of 9 ℓ per minute was first turned on for 4 minutes before Tap G was turned on as well. If the tank was filled to the brim in a total of 5 minutes from the time when Tap F was first turned on, what is the rate at which Tap G fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the container
= 86 x 60 x 36
= 185760 cm
3 1 ℓ = 1000 cm
3 9 ℓ = 9000 cm
3 Volume of water filled by Tap F
= 9000 x 5
= 45000 cm
3 Volume of water filled by Tap G
= 185760 - 45000
= 140760 cm
3 Rate in which Tap G fills the container
= 140760 ÷ 1
= 140760 cm3/min
140760 mℓ/min
= 140.76 ℓ/min
≈ 140.8 ℓ/min (Correct to 1 decimal place)
Answer(s): 140.8 ℓ/min