Complex sentence: Burgula Ramakrishna Rao was first chief minister of the Hyderabad state from 1952 to 1956 when the region was merged with the Andhra state to form present day Andhra Pradesh State.
Split into simpler sentences: Burgula Ramakrishna Rao was first chief minister of the Hyderabad state from 1952 to 1956. And in 1956, Hyderabad State was merged with the Andhra state to form the present day Andhra Pradesh State.