Question

Form all the four digits number that can be formed using the digits $1,2,3and4$.taking each digits only once at thousand place.

Answer 1

Finding all four digits number is as follows:-

The digits can be arranged in the following ways:-

a) On keeping $1$at thousand places, the numbers are $1234,1243,1324,1342,1432,$ and $1423.$

b) On keeping $2$ at thousand places, the numbers are $2134,2143,2314,2341,2431,$ and $2413.$

c) On keeping $3$ at thousand places, the numbers are$3124,3142,3214,3241,3421$, and $3412$

d) On keeping $4$ at thousand places, the numbers are$4123,4132,4213,4231,4321,$ and $4312$

Hence, all the four digits numbers that can be formed using the digits are $1234,1243,1324,1342,1432,1423,2134,2143,2314,2341,2431,2413,3124,3142,3214,3241,3421,3412,4123,4132,4213,4231,4321,4312$