A rectangular container measuring 86 cm by 56 cm by 30 cm was to be filled with water by two taps, H and J. Tap H which fills the tank at a rate of 6 ℓ per minute was first turned on for 3 minutes before Tap J was turned on as well. If the tank was filled to the brim in a total of 6 minutes from the time when Tap H was first turned on, what is the rate at which Tap J fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the container
= 86 x 56 x 30
= 144480 cm
3 1 ℓ = 1000 cm
3 6 ℓ = 6000 cm
3 Volume of water filled by Tap H
= 6000 x 6
= 36000 cm
3 Volume of water filled by Tap J
= 144480 - 36000
= 108480 cm
3 Rate in which Tap J fills the container
= 108480 ÷ 3
= 36160 cm3/min
36160 mℓ/min
= 36.16 ℓ/min
≈ 36.2 ℓ/min (Correct to 1 decimal place)
Answer(s): 36.2 ℓ/min