Town X has 50,000 residents, some of whom were bom in Town X. What percent of the residents of Town X were bom in Town X?
(1)Of the male residents of Town X, 40 percent were not bom in Town X.
(2)Of the female residents of Town X, 60 percent were bom in TownX.
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
EACH statement ALONE is sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
谁知道有没有无性别者呢。
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设男性人数为x,女性人数为50000-x,则在列出生在town x的人数的式子为:0.6x+0.6*(50000-x)=0.6*50000,0.6x在式子中是可以消掉的,所以结合可求C
male里 born的比例和 female born的比例是一样的,就无所谓他们各自在town里面的比例不一样了
not bom …… 每次做题眼睛都不好使了