GWD一道逻辑 thx~

myungryong

38: GWD-29-Q35
In Patton City, days arecategorized as having heavy rainfall (more than two inches), moderate rainfall(more than one inch, but no more than two inches), light rainfall (at least atrace, but no more than one inch), or no rainfall.  In 1990, there were fewer days with lightrainfall than in 1910 and fewer with moderate rainfall, yet total rainfall forthe year was 20 percent higher in 1990 than in 1910.
If the statements aboveare true, then it is also possible that in Patton City
A.     the number of days with heavy rainfall was lower in 1990than in 1910
B.     the number of days with some rainfall, but no more than twoinches, was the same in 1990 as in 1910
C.     the number of days with some rainfall, but no more than twoinches, was higher in 1990 than in 1910
D.     the total number of inches of rain that fell on days withmoderate rainfall in 1990 was more than twice what it had been in 1910
E.      the average amount of rainfall per month was lower in 1990than in 1910
怎么会选A啊，明明M,L都减少了，总量上升。 H怎么可能还回更少呢？求解~~

vespertine612

文中只提到小雨和中雨，关键决定因素，只要选出明确说道“大雨”两个字的

选项就好了，否则这道题就没有任何约束能力，可以无穷尽地随你想下去了

myungryong

我的意思是，单纯凭借中雨是达不到两倍的，但是，如果加上大雨不就行了吗，既然D没说大雨量，就说明有可能啊

tclzcja

D is wrong

Firstly, assume the morderate total rainfall in 1910 as M1 and the

numbers of days with morderate rainfall as D1, the same as M2 and D2.

Now we can see that:
D1>D2
M1=D1*A1;M2=D2*A2 (A rangs from 1 to 2)

Then maximum M2 and minimum M1 as possible as above with limit.
D1=D2
A1=1 A2=2

SO
M2=2M1; and M2 can never be more than 2M1

myungryong

我还是觉得这道题有问题，既然说的是一种可能情况，其它选项也是有可能的，既然A没有挑明大雨量，其他没提到大雨的也可以说隐含着大雨量1900年的大，总之觉得这道题还是有很大缺陷，我觉得只有明确指出来大雨量>1910年才是对的，既然是possible就是说选项里任何的条件都不是绝对的，那其他选项也都是对的了~随便举个例子，比如D，开始很多人反对D是因为说即使极端状况 中雨量也不能达到2倍，那我也可以说，这是在题目允许状况下的一个Possible情况，我可以在中雨1.9倍的情况下，大雨2倍多不就行了吗~既然都没说明，为什么就说这个错呢？？

myungryong

谢谢楼上2位。雨量这个事情我知道是这个题的point所在。错因的确是it is also possible的原因，当成assumption来做了，惯性思维找logical gap了

soubixl

举个极端例子  1990年 某一天下了场特大暴雨 一天的雨量就等于1990全部高

雨量日的总和了

lshlccER

注意是问 it is also possible that  也就是说选一个有可能发生的情况。注意天数与雨量，不要忽略了每次下的雨量。
总雨量=天数*平均雨量
A之所以有可能是因为有可能在1990年下大雨的总量>1910的。