选择题
2001 AMC 8 Problem 24: Folded Colored Triangle Pairs
Each half of this figure is composed of 3 red triangles, 5 blue triangles and 8 white triangles. When the upper half is folded down over the centerline, 2 pairs of red triangles coincide, as do 3 pairs of blue triangles. There are 2 red-white pairs. How many white pairs coincide?
A.
4
B.
5
C.
6
D.
7
E.
9