26 Running at their respective constant rates, machine X takes 2 days longer to produce w widgets than machine Y. At these rates, if the two machines together produce 5/4 w widgets in 3 days, how many days would it take machine X alone to produce 2w widgets?
A. 4 B. 6 C. 8 D. 10 E. 12 这道题目做不出来,有没有人帮忙讲一下如何计算?? 30. Joanna bought only $0.15 stamps and $0.29 stamps. How many $0.15 stamps did she buy? (1) She bought $4.40 worth of stamps. (2) She bought an equal number of $0.15 stamps and $0.29 stamps 这道题目我觉得(1)中0.15X+0.29Y=4.4,X,Y both are positive integer,请问除了用具体数字试以外 有怎么样的好点方法来确定有没有整数解啊? 另外我选了A 答案选D,是不是答案有问题啊? 35 What is the median number of employees assigned per project for the projects at Company Z? (1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project. (2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project. 这道题目答案选了C 但是我觉得题目中的4 or more还有2 or more本身就是一个不确定的数字,最后求出的median也就是 4 or more/2 or more,这样的结果最终没有给出median是多少,所以我觉得选E啊 高手执教
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