Question 916754
Use the formula

P =  n!/(n- r)!
 
   Example  5! = 5*4*3*2*1  for factorial !
   


=   10! /  (10-6)! 


    10! /  4!   

=   (10*9*8*7*6*5*4!)/ 4!
 
=   90*56*30 =  151,200 ways