The way you put it is confusing. I'll answer but the way you put it was confusing to me.
Answer:
1,100 is the answer.
Step-by-step explanation:
Since the difference of the subtraction problem is 1,103, when it is rounded, it becomes 1,100.

The equation of circle in standard form can be represented as :

where,
- h = x - coordinate of centre = 0
- k = y - coordinate of centre = 0
- r = radius of circle = 6 units
now, let's plug in the values :


That's the required equation of circle.
The radius of the circle is 3