A rectangular tank measuring 76 cm by 60 cm by 36 cm was to be filled with water by two taps, N and P. Tap N which fills the tank at a rate of 5 ℓ per minute was first turned on for 2 minutes before Tap P was turned on as well. If the tank was filled to the brim in a total of 6 minutes from the time when Tap N was first turned on, what is the rate at which Tap P fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the tank
= 76 x 60 x 36
= 164160 cm
3 1 ℓ = 1000 cm
3 5 ℓ = 5000 cm
3 Volume of water filled by Tap N
= 5000 x 6
= 30000 cm
3 Volume of water filled by Tap P
= 164160 - 30000
= 134160 cm
3 Rate in which Tap P fills the tank
= 134160 ÷ 4
= 33540 cm3/min
33540 mℓ/min
= 33.54 ℓ/min
≈ 33.5 ℓ/min (Correct to 1 decimal place)
Answer(s): 33.5 ℓ/min