选择题
2009 AMC 8 Problem 18: Tiled Floor Pattern
The diagram represents a 7-foot-by-7-foot floor that is tiled with 1-square-foot black tiles and white tiles. Notice that the corners have white tiles. If a 15-foot-by-15-foot floor is to be tiled in the same manner, how many white tiles will be needed?
A.
49
B.
57
C.
64
D.
96
E.
126