A rectangular container measuring 76 cm by 51 cm by 32 cm was to be filled with water by two taps, R and S. Tap R which fills the tank at a rate of 9 ℓ per minute was first turned on for 3 minutes before Tap S was turned on as well. If the tank was filled to the brim in a total of 6 minutes from the time when Tap R was first turned on, what is the rate at which Tap S fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the container
= 76 x 51 x 32
= 124032 cm
3 1 ℓ = 1000 cm
3 9 ℓ = 9000 cm
3 Volume of water filled by Tap R
= 9000 x 6
= 54000 cm
3 Volume of water filled by Tap S
= 124032 - 54000
= 70032 cm
3 Rate in which Tap S fills the container
= 70032 ÷ 3
= 23344 cm3/min
23344 mℓ/min
= 23.344 ℓ/min
≈ 23.3 ℓ/min (Correct to 1 decimal place)
Answer(s): 23.3 ℓ/min