Convention Followed here:-Those things in ( ) can be permute in any order. Except bracket all no. are fixed
Here 2 cases occur
(Means first 4 item permutable and last 2 item fixed)
Due to mod 10 function they will always go to their unit position Bucket
so 4!=24 Insertion Sequence possible.
To get more insertion sequence we compulsory put 52 as 4th item in insertion sequence which will be different from above 24 insertion sequence bcz in those 24 sequence 52 always comes as 5th item of insertion sequence where as here it comes as 4th item of insertion Sequence.
So 3!= 6 possibilities
So total case1+case2=24+6= 30 possibilities.