A rectangular tank measuring 81 cm by 58 cm by 29 cm was to be filled with water by two taps, B and C. Tap B which fills the tank at a rate of 6 ℓ per minute was first turned on for 4 minutes before Tap C was turned on as well. If the tank was filled to the brim in a total of 5 minutes from the time when Tap B was first turned on, what is the rate at which Tap C fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the tank
= 81 x 58 x 29
= 136242 cm
3 1 ℓ = 1000 cm
3 6 ℓ = 6000 cm
3 Volume of water filled by Tap B
= 6000 x 5
= 30000 cm
3 Volume of water filled by Tap C
= 136242 - 30000
= 106242 cm
3 Rate in which Tap C fills the tank
= 106242 ÷ 1
= 106242 cm3/min
106242 mℓ/min
= 106.242 ℓ/min
≈ 106.2 ℓ/min (Correct to 1 decimal place)
Answer(s): 106.2 ℓ/min