A rectangular container measuring 86 cm by 59 cm by 35 cm was to be filled with water by two taps, E and F. Tap E which fills the tank at a rate of 9 ℓ per minute was first turned on for 2 minutes before Tap F was turned on as well. If the tank was filled to the brim in a total of 7 minutes from the time when Tap E was first turned on, what is the rate at which Tap F fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the container
= 86 x 59 x 35
= 177590 cm
3 1 ℓ = 1000 cm
3 9 ℓ = 9000 cm
3 Volume of water filled by Tap E
= 9000 x 7
= 63000 cm
3 Volume of water filled by Tap F
= 177590 - 63000
= 114590 cm
3 Rate in which Tap F fills the container
= 114590 ÷ 5
= 22918 cm3/min
22918 mℓ/min
= 22.918 ℓ/min
≈ 22.9 ℓ/min (Correct to 1 decimal place)
Answer(s): 22.9 ℓ/min