It takes Faucet R 15 minutes to fill a container measuring 20 cm by 8 cm by 14 cm completely while it takes Faucet D only 10 minutes. How long will it take to completely fill the container with water if both faucets are turned on at the same time and 3 cubic cubes of edges 5 cm, filled with water, are poured into the container? Leave the answer in minutes and round off to 2 decimal places.
Time taken by Faucet R to fill the container:

15 min → 1 tank
1 min → ¹₁₅ tank

Time taken by Faucet D to fill the container:
10 min → 1 tank
1 min → ¹₁₀ tank

Volume of the container
= 20 x 8 x 14
= 2240 cm³

Volume of 3 cubic cubes
= 3 x (5 x 5 x 5)
= 375 cm³

Time taken by Faucet R and Faucet D to fill a container:
1 min → ¹₁₅ + ¹₁₀ =⁵₃₀ = ¹₆ container

¹₆ container → 1 min
1 container → 1 ÷ ¹₆ = 1 x ⁶₁ = 6 min

Remaining volume of the container to be filled by both faucets 
= 2240 - 375
= 1865 cm³

Time taken to fill the container
= ¹⁸⁶⁵₂₂₄₀ x 6
= 4.9955357142857
≈ 5 min

Answer(s): 5 min