What percentage of estate is inherited by nephews if uncle dies without living siblings or a Will?

When one dies without a Will, the rules of intestate succession determine inheritance.  Intestate means dying without a Will.

If your uncle died, but had a surviving spouse, she gets the entire estate and the nephews get nothing.  If there is no surviving spouse, but there are surviving children, those children of your aunt and uncle inherit equal shares of the estate.  For example, if there were two surviving children, they would each receive one half and the nephews would receive nothing.  If there is a deceased child of your aunt and uncle who had children, those children (your aunt and uncle's grandchildren) would receive their deceased parent's share of the estate which would be divided among them.  If there is no surviving spouse, no surviving children, no surviving parents of your uncle and no surviving siblings, then the nephews would divide the share that their parent (brother and sister) would have received.  If the brother would have received one half and the sister would have received one half of the estate, then the seven nephews would inherit as follows:  The sister's children would each receive one half of her share since the sister had two children.  The brother's children would each receive one fifth of his share since the brother had five children.