数学较弱，问一下 QYQ sec1 37

fengyun1

 

QYQ sec1 37

In township K, 1/5 of the housing units are equipped with cable television. If 1/10 of the housing units, including 1/3 of those that are equipped with cable television, are equipped with videocassette recorders, what fraction of the housing units have neither cable television nore videocassette recorders?

 

a.23/30    b.11/15   c.7/10   d.1/6   e.2/15

 

答案是A。1-（1/5）-（1/10）+1/15

为什么不是1-（1/5）-（1/10）+1/30？

listen2000

以下是引用fengyun1在2006-9-15 11:30:00的发言：
 

QYQ sec1 37

In township K, 1/5 of the housing units are equipped with cable television. If 1/10 of the housing units, including 1/3 of those that are equipped with
            cable television, are equipped with videocassette recorders, what fraction of the housing units have neither cable television nore videocassette recorders?

 

a.23/30    b.11/15   c.7/10   d.1/6   e.2/15

 

答案是A。1-（1/5）-（1/10）+1/15

为什么不是1-（1/5）-（1/10）+1/30？

including 1/3 of ....... cable television.  NOT 1/3 of ........ videocassette recorders

fengyun1

看了润发的解答，真有种aha的感觉。理解题意很关键呀！！！

 

谢谢。

[此贴子已经被作者于2006-9-16 12:25:27编辑过]

jessie128

1/3 of ........ videocassette recorders,如果是这种描述的话，那这句或就没有意义了，所以，我认为是在including 1/3 of ....... cable television. 这种情况下，关键是看里面的Those怎样理解，如果理解为videocassette recorders的话，那就应该是搂主说的这种答案。本人赞同搂主的答案即11/15。

Dr.Heisenberg

including 1/3 of those ....  
Here "those" modifies "households that are equipped with cable television" instead of "households equipped with recorders".
Did I understand correctly?