A rectangular container measuring 85 cm by 60 cm by 24 cm was to be filled with water by two taps, V and W. Tap V which fills the tank at a rate of 8 ℓ per minute was first turned on for 3 minutes before Tap W was turned on as well. If the tank was filled to the brim in a total of 7 minutes from the time when Tap V was first turned on, what is the rate at which Tap W fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the container
= 85 x 60 x 24
= 122400 cm
3 1 ℓ = 1000 cm
3 8 ℓ = 8000 cm
3 Volume of water filled by Tap V
= 8000 x 7
= 56000 cm
3 Volume of water filled by Tap W
= 122400 - 56000
= 66400 cm
3 Rate in which Tap W fills the container
= 66400 ÷ 4
= 16600 cm3/min
16600 mℓ/min
= 16.6 ℓ/min
≈ 16.6 ℓ/min (Correct to 1 decimal place)
Answer(s): 16.6 ℓ/min