111 * 111 = 12321. How?

11 * 11 = 121

1111 * 1111 = 1234321.

Can you the understand the logic of this multiplication.Its simple. For example, take 

1111 * 1111 as A* B ;

•  Now the element in A is same as element in B
• The number of elements in A are same as elements in B
• All the elements in A and B are 1
• For multiplying this, first consider how many elements are there in A. So in our case its four.
• So the answer, first go in ascending order 1 2 3 4 then come in descending order 3 2 1.
• Combine both the values 1 2 3 4 3 2 1.
• Thats the answer

Ex: 111 111 111 * 111 111 111 =  1 2 3 4 5 6 7 8 9 8 7 6 5 4 3 2 1 [Number of elements are nine]

Hope you got the logic.. Any doubt, Buzz me