A rectangular container measuring 74 cm by 58 cm by 31 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 4 minutes before Tap W was turned on as well. If the tank was filled to the brim in a total of 6 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
= 74 x 58 x 31
= 133052 cm
3 1 ℓ = 1000 cm
3 8 ℓ = 8000 cm
3 Volume of water filled by Tap V
= 8000 x 6
= 48000 cm
3 Volume of water filled by Tap W
= 133052 - 48000
= 85052 cm
3 Rate in which Tap W fills the container
= 85052 ÷ 2
= 42526 cm3/min
42526 mℓ/min
= 42.526 ℓ/min
≈ 42.5 ℓ/min (Correct to 1 decimal place)
Answer(s): 42.5 ℓ/min