arrangements preserving the effect of first pass partition algorithm are

Question

consider an array consisting of following elements in an unsorted order but 60 as first element 60,80,15,95,7,12,35,90,55 quick sort partition algorithm is applied by choosing first element as pivot total number of arrengements of array integers is possible preserving the effect of first pass of partition algorithm are

 

Answer 1

first choosing 60 as pivot element and applying first pass of Quick Sort we get 

55 15 7 12 35 60 80 90 95.

Now left side of 60 can be arrange in 5! and right side can be arrange in 3! ways.

Total ways=5!*3!=720