A rectangular container measuring 80 cm by 51 cm by 25 cm was to be filled with water by two taps, K and L. Tap K which fills the tank at a rate of 7 ℓ per minute was first turned on for 2 minutes before Tap L was turned on as well. If the tank was filled to the brim in a total of 7 minutes from the time when Tap K was first turned on, what is the rate at which Tap L fills the tank? Give your answer in ℓ per minute correct to 1 decimal place.
Total volume of the container
= 80 x 51 x 25
= 102000 cm
3 1 ℓ = 1000 cm
3 7 ℓ = 7000 cm
3 Volume of water filled by Tap K
= 7000 x 7
= 49000 cm
3 Volume of water filled by Tap L
= 102000 - 49000
= 53000 cm
3 Rate in which Tap L fills the container
= 53000 ÷ 5
= 10600 cm3/min
10600 mℓ/min
= 10.6 ℓ/min
≈ 10.6 ℓ/min (Correct to 1 decimal place)
Answer(s): 10.6 ℓ/min