A oct JJ

cook

ask for help and thanks!
16、DS
The number of boys in a class and the number of the totle of boys and girls who take the course of biology is shown in the form blew, How many is all the boys and girls in the class.
表格 take biology not take biology totle
----------------------------------------------------------
boy 28
----------------------------------------------------------
girl
----------------------------------------------------------
totle 36
1. There are 3 boys who do not take biology
2. The girls in the class is twice as many as the totle of boys and girls who do not take biology
-------------------------------------
C  or B
==================================
But I think E. Basically I think the problem stem from the unclear question.

yiyaya

设班级人数为x, 则根据条件2， x-28=2*(x-36), x=44, so B is right.

cook

ok, got B for sure.

tongxun

原来的图形不对，你再看看我重新修改过的图。

tongxun

cook：这个题目的图形在转来的时候有些变行。我现在拷贝不过来。自己画一个咱们讨论讨论。
     take   not take   totle
----------------------------------
boy、、、、、、、 28
-----------------------------------------
girl
---------------------------------
totle、36
--------------------------------
现在咱们填填空：
     take    not take    totle
-------------------------------------------------------------
boy、 25、  3 、        28
-------------------------------------------------------------
girl、11、 X 、        11+X
--------------------------------------------------------------
totle、36、3+X
--------------------------------------------------------------
（11+X）=2（3+X）
X=5，  所以总人数为：16+28=44

抱歉！

[此贴子已经被tongxun于2002-10-12 10:06:59编辑过]

[此贴子已经被tongxun于2002-10-12 13:26:25编辑过]

[此贴子已经被tongxun于2002-10-12 13:27:14编辑过]

ruthy_yin

B
设女孩总数为x
x = 2 （x + 28 -36)
=〉x=16

tongxun

不行，图形还是改了。我再调整调整。

cook

Very clear ! thanks.