There are 10 persons named P1,P2,P3,....,P10. Out of 10 persons, 5 persons are to be arranged in a line such that is each arrangement P1 must occur whereas P4 and P5 do not occur. Find the number of such possible arrangements.
Total persons = 10
Number of persons to be selected = 5
Condition = p1 must and p4, p5 must not be there
Remaining number of persons required is 4 out of 10 - 3 = 7
7C4×5!