标题: 请教几道XDF蓝皮书上的数学题~谢谢大家了！ [打印本页] 作者: catharine6699 时间: 2010-8-17 23:31 标题: 请教几道XDF蓝皮书上的数学题~谢谢大家了！ 1。p226第26题 是一道DS题 The ratio of the number of women to the number of men to the number of children in a room is 5:2:7, respectively. What is the total number of people in the room? (1)The total number of women and children in the room is 12 (2)There are fewer than 4 men in the room 答案竟然是D，我觉得第二个条件不能单独出来的啊
2。p225第22题 A jewelry dealer initialy offered a bracelet for sale at an asking price that would give a profit to the dealer of 40 percent of the original cost. What was the original cost of the bracelet? (1) After reducing this asking price by 10 percent, the jewelry dealer sold the racelet at a profit of $403. (2)The jewelry dealer sold the bracelet for $1953. 答案是A，但是我觉得第二个条件可以算出来啊！40%c+c=1953 就可以得出c 3。If the number of square units in the area of circle C is twice the number of linear units in the circunference of C, what is the number of square units in the area? 谁能帮我翻译一下啊~我题目读不懂哦！作者: scholar 时间: 2010-8-18 00:08
对于1题 （2）说男的少于4个人那无非是1 2 3 然后利用比例关系 会发现只有取2 才会得到整数解的女人 孩子的人数。 对于2题 我估计The jewelry dealer sold the bracelet for $1953.中未言明是否是an asking price 所以就不确定了 仅供参考！！！！