A rectangular tank measuring 82 cm by 53 cm by 23 cm was to be filled with water by two taps, J and K. Tap J which fills the tank at a rate of 5 ℓ per minute was first turned on for 3 minutes before Tap K was turned on as well. If the tank was filled to the brim in a total of 5 minutes from the time when Tap J was first turned on, what is the rate at which Tap K fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the tank
= 82 x 53 x 23
= 99958 cm
3 1 ℓ = 1000 cm
3 5 ℓ = 5000 cm
3 Volume of water filled by Tap J
= 5000 x 5
= 25000 cm
3 Volume of water filled by Tap K
= 99958 - 25000
= 74958 cm
3 Rate in which Tap K fills the tank
= 74958 ÷ 2
= 37479 cm3/min
37479 mℓ/min
= 37.479 ℓ/min
≈ 37.5 ℓ/min (Correct to 1 decimal place)
Answer(s): 37.5 ℓ/min