Rearrange 1234 so that it is divisible by 11, how many different such possibilities exist?

Question

1234 divided by 11 is not a whole number but if you rearrange the digits it is possible to find a number that divides by 11 to give a whole number. How many different ways can you find to do this?

Answer 1

1243, 1342, 2134, 2431, 3124, 3421, 4213, 4312 are all divisible by 11 [ 8 NOS ]
The trick here is to use the fact that the numbers divisible by 11 have a special property where in the sum of their digits in the even places = sum of their digits in the odd places. ie., for 1243 ===> 1 + 4 = 5 = 3 + 2.