[問題]舊PP的一題

[lunar916]

Of the 4,800 voters who voted for or against Resolution K, 1800 were Democrats and 3,000 were Republicans. What was the total number of female voters who voted for Resolution K?

1)3/4 of the Democrats and 2/3 of the Replublicans voted for Resolution K
2)1/3 of the Democrats who voted for Resolution K and 1/2 of the Replublicans who voted for Resolution K were females


ans:
C
=====
可是我不懂的是說,題目已說明有1800跟3000 of Democrats and Republicans voted respectively
我從1/3 x 1800 跟 1/2 x 3000 不就得出答應了嗎?
那為何不是選B呢?

[waleaaa]

條件(2)是說─
在投票贊成K方案且是Democrats的人中　1/3是女性
而投票贊成K方案且是Republicans的人中 1/2是女性
所以需要條件(1)才可知有多少Democrats及Republicans投票支持K方案
即　1800 * 3/4 * 1/3 + 3000 * 2/3 * 1/2　故選C

[lunar916]

條件(2)是說─
在投票贊成K方案且是Democrats的人中　1/3是女性
而投票贊成K方案且是Republicans的人中 1/2是女性
所以需要條件(1)才可知有多少Democrats及Republicans投票支持K方案
即　1800 * 3/4 * 1/3 + 3000 * 2/3 * 1/2　故選C

喔~~~~~~
我看到我的問題了~
Of the 4,800 voters who voted for or against Resolution K,
也就是所有有投票的人~
我一直以為是只有投給resolution K的人
感謝感謝~