Didnt understood the problem

After prateek bhaiya divides the coins into two parts, how come its possible that all the coins having head gets equally divided??

@Shivam01 After dividing it into 2 partitions he has x tails and 20-x tails in both sets.
Now if he flips all coins of 20-x set he would have x tails again . So both sets contain same no of heads and tails.