A rectangular container measuring 72 cm by 58 cm by 27 cm was to be filled with water by two taps, Z and A. Tap Z which fills the tank at a rate of 8 ℓ per minute was first turned on for 4 minutes before Tap A was turned on as well. If the tank was filled to the brim in a total of 5 minutes from the time when Tap Z was first turned on, what is the rate at which Tap A fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the container
= 72 x 58 x 27
= 112752 cm
3 1 ℓ = 1000 cm
3 8 ℓ = 8000 cm
3 Volume of water filled by Tap Z
= 8000 x 5
= 40000 cm
3 Volume of water filled by Tap A
= 112752 - 40000
= 72752 cm
3 Rate in which Tap A fills the container
= 72752 ÷ 1
= 72752 cm3/min
72752 mℓ/min
= 72.752 ℓ/min
≈ 72.8 ℓ/min (Correct to 1 decimal place)
Answer(s): 72.8 ℓ/min