Share of son in father's property

Hi sirs,

I have a few questions regarding my father's share in my grandfather's property.

Background:

My Grandfather died(natural death) not leaving behind any will. 1 Shop was there which was purchsed by my father and grandfather in paternership.

My father was having 60% share and grandfather was having 40% share at the time of purchase, as per the purchase agreement.

My father also died.

My grandfather totally 4 children: 3 daughters and 1 son(my father).

Now we have selled the shop for 14 lacs.

Question:

1) What is my father's total share in the shop ? is it only 60% which is written in the purchase document of the shop or is it 60% share(as per the purchase document) + 1/4th of the remaining 40% (i.e., 8.4 lacs or 8.4+1.4=9.8 lacs) ? Please advice.

Thanks in Advance for your Help,

Ravi Pinjani.