【Question 4】
A father wants to divide his property among his children: first, he gives 1000 yuan and $\frac{1}{10}$ of the remaining property to the eldest child, then 2000 yuan and $\frac{1}{10}$ of the remaining property to the second child, then 3000 yuan and $\frac{1}{10}$ of the remaining property to the third child, and so on. It turns out that each child receives the same amount of property. The father has $\qquad$ children.