To fill a tank measuring 60 cm by 40 cm by 50 cm completely, it takes Tap E 4 minutes while it takes Tap F only 12 minutes. How long will it take to completely fill the container with water if both the taps are turned on at the same time and 6 cubic containers of edges 10 cm, filled to the brim with water are poured into the tank?
Volume of the tank 
= 60 x 40 x 50
= 120000 cm³

Volume of 6 containers
= 10 x 10 x 10 x 6
= 6000 mℓ

Remaining volume to be filled by the Tap E and Tap F 
= 120000 - 6000
= 114000 mℓ
= 114000 cm³

Fraction of the tank to be filled
= ¹¹⁴⁰⁰⁰₁₂₀₀₀₀
= ¹⁹₂₀

Tap E:
1 tank → 4 min
1 min → ¹₄ tank

Tap F:
1 tank → 12 min
1 min → ¹₁₂ tank

Tap E and Tap F:
1 min → ¹₄ + ¹₁₂ = ³₁₂ + ¹₁₂ = ¹₃ tank
1 tank → ³₁ min

¹⁹₂₀ tank → ³₁ x ¹⁹₂₀ = ⁵⁷₂₀ = 2.85 min

Answer(s): 2.85 min