A rectangular container measuring 75 cm by 52 cm by 20 cm was to be filled with water by two taps, C and D. Tap C which fills the tank at a rate of 5 ℓ per minute was first turned on for 3 minutes before Tap D was turned on as well. If the tank was filled to the brim in a total of 5 minutes from the time when Tap C was first turned on, what is the rate at which Tap D fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the container
= 75 x 52 x 20
= 78000 cm
3 1 ℓ = 1000 cm
3 5 ℓ = 5000 cm
3 Volume of water filled by Tap C
= 5000 x 5
= 25000 cm
3 Volume of water filled by Tap D
= 78000 - 25000
= 53000 cm
3 Rate in which Tap D fills the container
= 53000 ÷ 2
= 26500 cm3/min
26500 mℓ/min
= 26.5 ℓ/min
≈ 26.5 ℓ/min (Correct to 1 decimal place)
Answer(s): 26.5 ℓ/min