The US state of Montana is bordered by North Dakota and South Dakota to the east and the Rocky Mountains cover about 40 percent of Montana's land surface.
About 2/5ths or 40 percent Montana's land surface is covered by the Rocky Mountains. About 60 percent of Colorado's land surface is covered by the Rocky Mountains while Wyoming's land surface is about 75 percent mountains.
Montana
The state of Montana.
Montana borders North Dakota and South Dakota and also contains part of the Rocky Mountains.
No state listed borders the Rocky Mountains.
Montana borders North and South Dakota,
There is no country which borders both North Dakota and South Dakota. North Dakota shares a border with Canada.
The US state of Montana's eastern borders are North Dakota and South Dakota.
South Dakota
The US state which borders North Dakota on the west is Montana.
The answer is South Dakota. Kentucky borders Tennessee to the north. South Dakota borders Nebraska to the north.
The US state of Minnesota borders North Dakota and part of South Dakota on their eastern borders and the US state of Montana borders North Dakota and part of South Dakota on their western borders.