Using Genesis's dimensions, Noah's Ark had a length-to-width ratio of 6 to 1.
Genesis 6:15 gives the Ark as 300 cubits long and 50 cubits wide. Dividing 300 by 50 produces a ratio of 6:1, independent of the modern length chosen for the cubit.
This proportion is often discussed in connection with stability. A long, broad, box-like vessel can resist rolling, although the Genesis account does not present a modern naval-architecture analysis or specify how the Ark was propelled or steered.
The ratio should not be confused with the height-to-width relationship, which is 30 to 50, or 3:5. All three dimensions come from the same verse, but only the first two are needed to calculate the 6:1 length-to-width figure.