Question 666715
<pre>
Either
1 of them is free of defect or 
2 of them are free of defect or
3 of them are free of defect or
4 of them are free of defect or
5 of them are free of defect or
6 of them are free of defect or
7 of them are free of defect or
8 of them are free of defect or
9 of them are free of defect or
10 of them are free of defect or
11 of them are free of defect or
all 12 of them are free of defect.

Or--

Not all of them are defective. 

Edwin</pre>