After winning the toss, Railways elected to bat first and Mithali's 100-run effort was complemented by Asha Rawat's 50 not out taking them to a competitive 264 for three in 50 overs.
In reply, East Zone were skittled out for 87 in 47 overs as Reema Malhotra picked up four wickets for 38 runs. She was well supported by Sangita and Nooshin-Al Khadeer, who took three wickets apiece.
Lovely Raj was the only East Zone batter to put up some fight with 29 runs.
In another match, North Zone's decision to bat first proved to be a disaster as they were bowled out for 124 in 40 overs against West Zone, who reached the target in 36.4 overs for the loss of four wickets. Poonam Raut (46) and Amita Patil (57) were the top scorers for the winners.
Meanwhile, in another low scoring encounter, South Zone beat Air India by six wickets after restricting them to 162 for eight. Anjum Chopra scored 48 not out to to take Air India to victory in 36.5 overs with six wickets in hand.