gwd第一套中的,if 10的50次方-74 is written as an integer in base 10 notation,what is the sum of the digits in that interger。答案有 424 433 440 449 467. 大家能帮忙解释一下题干吗?
还有一道题,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 5/4w widgets in 3 days,how many days would it take machine X alone to produce 2w widgets。答案有4 6 8 10 12.
感觉好绕,没弄清楚意思,希望大家帮帮忙作者: james2201 时间: 2012-4-5 08:58