An estimate is 700000/350=2000 because 785 is close to 700 which is twice 350.
Another estimate is found by rounding 350 up to 400 and 785229 up to 800000, but this also comes to 2000.
A better estimate would be 770000/350=110000/50=11000/5=2200. In this case we noted that 7 goes into 35 and 77, and 770000 is close to 785229.