Convert from rai to hide

Unit Definition (rai)
The rai is a traditional unit of land area in Thailand. The rai is now considered to equal exactly 1600 square meters, which is 0.16 hectare or approximately 0.3954 acre. The rai is divided into 4 ngan. The unit is called the hai in northern Thailand and the lai in Laos. The word means "field," that is, an upland field rather than a rice paddy.

Unit Definition (hide)
The hide is a very old English unit of land area, dating from perhaps the seventh century. The hide was the amount of land that could be cultivated by a single plowman and thus the amount of land necessary to support a family. Depending on local conditions, this could be as little as 60 acres or as much as 180 acres (24-72 hectares). The hide was more or less standardized as 120 acres (48.6 hectares) after the Norman conquest of 1066. The hide continued in use throughout medieval times, but it is now obsolete. The unit was also known as the carucate.