So the probability of the first math class is 1/2.

(2) Solution: There are six kinds of arrangement methods:

1 and 8( 1) classes arrange math 1 class, and 8(2) classes can arrange 2 or 3 classes;

2.8 classes (1) are arranged for 2 classes of mathematics, and 8 classes (2) can be arranged for 1 and 3;

Class 3.8 (1) is arranged for math class 3, and class 8 (2) can be arranged for 1 and 2;

4.8(2) Classes are arranged in mathematical disciplines 1, and classes 8( 1) can be arranged in 2 or 3 subjects;

5.8(2) Class 2 is arranged with the second paragraph of mathematics, and Class 8 (1) can be arranged with 1 and 3 paragraphs;

6.8(2) Class arranges the third math section, and Class 8 (1) can arrange 1 and Section 2;

There are two arrangements for each class, so the arrangement of 12 does not conflict with the math classes of these two classes. therefore

The probability that the math classes of these two classes do not conflict =1/36×12 =1/3.