( 1)2/3
If three squares are only colored differently, then there are always 3X3X3=27 kinds of * * *.
There are only three colors, one is red, so there are three ways to choose two of the remaining colors:
Red, x, red, y; Red, x, y, red; ——————————— This is 3X2X2= 12.
Red, x, y, x; —————————————— This is 3X2=6.
( 12+6)/27=2/3
(2) The colors can be 2, 3 and 4.
Total * * * coloring method is 4x3x3 = 108.
Two kinds: choose two of the four colors, X, Y, X, Y; ————————————6X2= 12
P= 12/ 108= 1/9
3 kinds: Choose 3 kinds from 4, which is the same as the question (1), except that the first color can be any of the four colors, 4X 18.
P=2/3
Four species: fully arranged, P=24/ 108=2/9.
E=2/9+4/3+8/9=28/9
exceed