Hey everyone 90 combinations is the wrong answer. The number of combinations which could be formed from these numbers are:

10*9*8*7*6*5*4*3*2*1= 3628800 combinations ---- as there are 10 numbers and the combinations could vary from a 1- digit number to a 10-digit number ...!!!!

10*9*8*7*6*5*4*3*2*1= 3628800 combinations ---- as there are 10 numbers and the combinations could vary from a 1- digit number to a 10-digit number ...!!!!