what is mean by permutation & combination?

Answer 1

Perhaps this will help:

SELECT 3 LETTERS FROM: {A, B, C, D}

4 Combinations
The ways that 3 letters can be selected where order doesn't matter.
(i.e., A,B,C is the same as A,C,B):
A, B, C
A, B, D
A, C, D
B, C, D

24 Permutations
The ways that 3 letters can be selected where the order matters.
(i.e., A,B,C is different from A,C,B):
A, B, C
A, B, D
A, C, B
A, C, D
A, D, B
A, D, C

B, A, C
B, A, D
B, C, A
B, C, D
B, D, A
B, D, C

C, A, B
C, A, D
C, B, A
C, B, D
C, D, A
C, D, B

D, A, B
D, A, C
D, B, A
D, B, C
D, C, A
D, C, B

{This shows that combination locks are really permutation locks! If 1-2-3-4 opens a lock, usually 2-1-3-4 doesn't open it.}

Those people who are saying there are more ways with a combination are getting it backwards! As I have just shown there are obviously more ways when order matters.

(Thats what you get for copying an answer "whoms"! You copied a wrong one. And after looking at your other answers, it looks like thats all you do: copy other answers.)

Answer 2

permutation is when u select in a perticular order. and combination is when the order does not matter. generally there is more ways to selection without an aorder thus combination will have higher number than a purmutation.

Answer 3

permutation is when u select in a perticular order. and combination is when the order does not matter. generally there is more ways to selection without an aorder thus combination will have higher number than a purmutation.

Answer 4

permutation=arrangement
combination=selection

Answer 5

the different ways in which one can order a set of things --permutation

combination-- joining of more than one thing to form a single unit

Answer 6

ACCESSING VARIOUS POSSIBILITIES