A rectangular tank measuring 90 cm by 53 cm by 27 cm was to be filled with water by two taps, D and E. Tap D which fills the tank at a rate of 5 ℓ per minute was first turned on for 3 minutes before Tap E was turned on as well. If the tank was filled to the brim in a total of 6 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 tank
= 90 x 53 x 27
= 128790 cm
3 1 ℓ = 1000 cm
3 5 ℓ = 5000 cm
3 Volume of water filled by Tap D
= 5000 x 6
= 30000 cm
3 Volume of water filled by Tap E
= 128790 - 30000
= 98790 cm
3 Rate in which Tap E fills the tank
= 98790 ÷ 3
= 32930 cm3/min
32930 mℓ/min
= 32.93 ℓ/min
≈ 32.9 ℓ/min (Correct to 1 decimal place)
Answer(s): 32.9 ℓ/min