A four digit number is squared to form an eight digit number. The center four digits of that square form the four digit number. Find all possible four digit numbers.

(If 'abcd' was the four digit number, then the eight digit number would look like 'wxabcdyz'.)

...."(If 'abcd' was the four digit number, then the eight digit number would look like 'wxabcdyz'.)

In the official solution the eight digit number would  not look like 'wxabcdyz':

2nd answer    would be   xaabcccc.   square of abcc  

and the 3rd answer    would be   cxabcccc, square of abcc  

SO ONLY THE 1st ANSWER QUALIFIES.

Edited on March 8, 2016, 8:14 pm

Posted by Ady TZIDON on 2016-02-24 08:33:25