A rectangular container measuring 84 cm by 52 cm by 36 cm was to be filled with water by two taps, D and E. Tap D which fills the tank at a rate of 9 ℓ per minute was first turned on for 4 minutes before Tap E was turned on as well. If the tank was filled to the brim in a total of 5 minutes from the time when Tap D was first turned on, what is the rate at which Tap E fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the container
= 84 x 52 x 36
= 157248 cm
3 1 ℓ = 1000 cm
3 9 ℓ = 9000 cm
3 Volume of water filled by Tap D
= 9000 x 5
= 45000 cm
3 Volume of water filled by Tap E
= 157248 - 45000
= 112248 cm
3 Rate in which Tap E fills the container
= 112248 ÷ 1
= 112248 cm3/min
112248 mℓ/min
= 112.248 ℓ/min
≈ 112.2 ℓ/min (Correct to 1 decimal place)
Answer(s): 112.2 ℓ/min