Between 1975 and 1985, nursing-home occupancy rates averaged 87 percent of capacity, while admission rates remained constant, at an average of 95 admissions per 1,000 beds per year. Between 1985 and 1988, however, occupancy rates rose to an average of 92 percent of capacity, while admission rates declined to 81 per 1,000 beds per year.
If the statements above are true, which of the following conclusions can be most properly drawn?
(A) The average length of time nursing-home residents stayed in nursing homes increased between 1985 and 1988.答案为A
(B) The proportion of older people living in nursing homes was greater in 1988 than in 1975.
(C) Nursing home admission rates tend to decline whenever occupancy rates rise.
(D) Nursing homes built prior to 1985 generally had fewer beds than did nursing homes built between 1985 and 1988.
(E) The more beds a nursing home has, the higher its occupancy rate is likely to be.

用排除法做对了,但还没想明白,请给我讲讲题干是什么意思?

我是这么理解的,假设就1000张床,每年来95 10年下来950,那要比87%的occupancy多,所以就的有人走

而85-95 同样1000张闯,每年来81个,10年810 要比92%的occupancy 少,所以就没人走,反而要多住一段时间,才能赶上92%的occupancy

在说一会自己都晕了

2楼的思路很清晰的.

我的思路和他略有不同:

Between 1975 and 1985, nursing-home occupancy rates averaged 87 percent of capacity, while admission rates remained constant, at an average of 95 admissions per 1,000 beds per year. Between 1985 and 1988, however, occupancy rates rose to an average of 92 percent of capacity, while admission rates declined to 81 per 1,000 beds per year.
If the statements above are true, which of the following conclusions can be most properly drawn?
(A) The average length of time nursing-home residents stayed in nursing homes increased between 1985 and 1988

此题应该为归纳吧.

分段考虑1)75年到85年,occupancy rates 87%, admission rate 95%.

          (2)85年到88年,or=92%,ar=81%.

问推出的结论:

那我们就找一个能合理解释这个现象的吧.

按照A所说,护士平局占用宿舍的时间有所提高.正好就是文章所支持的部分.

假设1000张床,(1)时间段,平均每年870人住在宿舍,有登记950入住.也就是说数量的差距是因为在这一年内有人在统计之前离开了宿舍.也就是住宿时间比较短.

             (2)时间段,920人住, 登记810入住.也就是说在这段时间每年登记的为810人,但是实际上宿舍有950人.为什么?有人住了一年还没走.结果实际占有数量就被累加了.造成总占有数量高于入住人数.

这道题的问题关键是看清楚admission rate和occupancy rate的区别.前者是指每年的入住率,后者是指实际宿舍人数.