Solution:
The answer is 3. In general, if at a certain point the grasshopper is at (a,b), at the previous step it was at a point (x,y) such that (a,b)=(x+y,y) or (a,b)=(x,x+y), that is, at (a−b,b) or at (a,b−a); moreover, if it started from a point (x0,y0) with positive coordinates, as the statement assures us, then at every moment it is located at a point with positive coordinates, and therefore the position preceding (a,b) is uniquely determined and is (a−b,b) if a>b, (a,b−a) if b>a.
It follows that the positions of the grasshopper preceding (2021,2050), going backwards, are: (2021,2050−2021)=(2021,29), (2021−29,29), (2021−2⋅29,29), …, (2021−69⋅29,29)=(20,29), (20,29−20)=(20,9). The grasshopper could therefore have started from (20,9); if it did not, it could have made one more jump and started from (20−9,9)=(11,9) or two more jumps and started from (11−9,9)=(2,9). If the grasshopper had made even more jumps, it would have started from a point whose second coordinate is at most 7, which does not satisfy the conditions of the statement. There are therefore 3 possibilities for (x0,y0).