Useful data, Thanks.
Let me point out that, nowadays measuring area of cultivated, un cultivated land,farm is easy with satellite mapping tools. Just locate the land in satellite maps, mark boundaries with marker tools provided, area is quickly calculated in various units like hectre, acre, sq meter, sq foot etc.
These tools are fairly accurate and saves time. The site I use regularly is given below. But you can find similar tools by searching for "google maps free land area calculator" in search engines.