A rectangular container measuring 82 cm by 60 cm by 35 cm was to be filled with water by two taps, G and H. Tap G which fills the tank at a rate of 7 ℓ per minute was first turned on for 3 minutes before Tap H was turned on as well. If the tank was filled to the brim in a total of 5 minutes from the time when Tap G was first turned on, what is the rate at which Tap H fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the container
= 82 x 60 x 35
= 172200 cm
3 1 ℓ = 1000 cm
3 7 ℓ = 7000 cm
3 Volume of water filled by Tap G
= 7000 x 5
= 35000 cm
3 Volume of water filled by Tap H
= 172200 - 35000
= 137200 cm
3 Rate in which Tap H fills the container
= 137200 ÷ 2
= 68600 cm3/min
68600 mℓ/min
= 68.6 ℓ/min
≈ 68.6 ℓ/min (Correct to 1 decimal place)
Answer(s): 68.6 ℓ/min