Given that 1 mutchkin (a scottish unit) = 0.42 L
Now the volume of container (assuming it to be cubical, as only one side is given) = a^3 = 1^3 = 1ft^3
Now 1 foot = 3.048 dm [1 decimeter= 0.1 m]
Hence 1 ft X 1ft X 1ft = 3.048 X 3.048 X 3.048 dm^3 = 28.32 dm^3
We know that 1L = 1 dm^3
therefore volume of container in Litres = 28.32 L
now as given that 0.42 L = 1 mutchkin
therefore 1 L = 1 / 0.42 mutchkin
28.32 L = 28.32 / 0.42 mutchkin = 67.43 mutchkins [This much mutchkin is required to fill the container]