Let a,b,c,d be real numbers such that (a−b)(c−d)(b−c)(d−a)=25. Find the sum of all possible values of (a−c)(b−d)(a−b)(c−d).
a=67, b=11, c=4, d=7
For first expression =2 /5
For 2nd expression =651 / 11
+143 
