A rectangular tank measuring 74 cm by 59 cm by 37 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 4 minutes before Tap M was turned on as well. If the tank was filled to the brim in a total of 5 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
= 74 x 59 x 37
= 161542 cm
3 1 ℓ = 1000 cm
3 6 ℓ = 6000 cm
3 Volume of water filled by Tap L
= 6000 x 5
= 30000 cm
3 Volume of water filled by Tap M
= 161542 - 30000
= 131542 cm
3 Rate in which Tap M fills the tank
= 131542 ÷ 1
= 131542 cm3/min
131542 mℓ/min
= 131.542 ℓ/min
≈ 131.5 ℓ/min (Correct to 1 decimal place)
Answer(s): 131.5 ℓ/min