Partition Of Undivided Properties

My mother died in 2002. Father remarried in 2003.We are two brothers out of first marriage and two sisters out of second marriage. One brother died in 2010.He did not marry. Then father died in 2017.Now we are four legal heirs->me stepmother and two stepsisters. Now in what ratio will the properties of father get divided?? And we will get the properties which are in the name of dead mother and brother??