A rectangular tank measuring 88 cm by 54 cm by 24 cm was to be filled with water by two taps, L and M. Tap L which fills the tank at a rate of 6 ℓ per minute was first turned on for 2 minutes before Tap M was turned on as well. If the tank was filled to the brim in a total of 6 minutes from the time when Tap L was first turned on, what is the rate at which Tap M fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the tank
= 88 x 54 x 24
= 114048 cm
3 1 ℓ = 1000 cm
3 6 ℓ = 6000 cm
3 Volume of water filled by Tap L
= 6000 x 6
= 36000 cm
3 Volume of water filled by Tap M
= 114048 - 36000
= 78048 cm
3 Rate in which Tap M fills the tank
= 78048 ÷ 4
= 19512 cm3/min
19512 mℓ/min
= 19.512 ℓ/min
≈ 19.5 ℓ/min (Correct to 1 decimal place)
Answer(s): 19.5 ℓ/min