Parity draw

(1). All units A and B may be 5*6=30 (species).

There are six even numbers of A and B, namely (2, 4), (4, 2), (2, 6), (6, 2), (4, 6) and (6, 4).

So P=6/30= 1/5.

Or the probability that A draws an even number is 3/6= 1/2, and the probability that B draws an even number is (3- 1)/(6- 1)=2/5.

So P= 1/2*(2/5)= 1/5.

(2) All units A and B may be 5*6=30 (species).

The serial number drawn by both parties is 5*2= 10 (species).

So the probability that A and B are not adjacent is P=20/30=2/3.