Right in joint property.

I purchased a plot of 700 square yards jointly with my cousin brother in Hapur(UP), in the year 2001. No share was specified in the registry. This land was agricultural land at the time of purchase. Later in 2002 a residential colony was developed around the plot, collectively by the land owners there. 235 yards of the plot became a part of the street passing through the plot. Now 218 yards of land was left on one side and 247 yards on other side of of street. A 100 yard piece of land adjoining the 247 yard plot was given to us in lieu of the land that went into the street without any paper work as this 100 yard piece of land falls in the same gata in which the 700 yards plot was lying . This plot was given by the person who had major share in the entire land around the plot. Now we were having 218 yards on one side of street and 347 yards on other side of street. My cousin brother sold the 218 yard plot on one side and 100 yards plot on other side i.e from 347 yards, without my knowledge. Now only 247 yard of plot is left on the site. Now in this plot of 247 yards, claim on 32 yards is made by my cousin.Now my querty is :- (1) Do the 100 yards plot transferred to us in lieu of the land that went into the street belongs to us legally.(2) What is my legal share in this plot of 247 yards.(3) How much can I sell from this 247 yards plot.(4) How should I proceed to claim my rightful share in the entire 700 yards plot.