It is known that there are three weak teams among the eight teams. By drawing lots, the eight teams were divided into two groups, A and B, with four teams in each group. The result was: (1) One of the two groups was just right.
Draw a tree with R for the weak team and Q for the strong team:
∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴∴875
∴ (1) The probability that one of the two groups A and B has exactly two weak teams is 68 = 34;
(2) The probability that there are at least two weak teams in Group A is 48 = 12.