cook

tongxun

cook: the questions in following are what you asked me to check.

1.DS有图。
说三角形ABC（逆时针）AB与X轴平行BC与Y轴平行。求B点横坐标。
1.A(-1,2)
2.C(8,10)
答案：B *************---> C
----------------------------
yes, you are right!
============================
9.A,B两公司卖馒头，98年A公司比B公司卖的馒头多，99年和00年A，B两公司分别比本公司前一年多卖了3%的馒头，问A，B两公司在00年卖的馒头差比他们在98年卖的馒头差增长了多少？
答案：6.09% **********----> How do you get it? ??????/
--------------------------------------
1) 00年卖的馒头差:A(1+3%)^2 - B(1+3%)^2
2) 98年卖的馒头差: A-B
3)馒头差增长了多少？:[ A(1+3%)^2 - B(1+3%)^2 -(A-B)]/(A-B)
                    =(1+3%)^2 -1
                    = 2*0.03 + 0.03^2
                    = 0.06 + 0.0009
                    =0.0609
0.0609 * 100=6.09%
================================================
11.DS
一四边形KPMQ（逆时针方向），四边相等。求KM？
1.KP=2
2.PQ=2
答案：C **************-----> D
-----------------------------------------
You are right too. I forgot the condition 四边相等.
================================
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 *************-->E
------------------------

==================================
4. To go a 405 miles trip, a car can go 36 miles per gallon for gasoline A , and for gasoline B, the efficiency decreased by 1/3 of A, ask during this trip, the car can save how many gallon of gasoline A for whole trip than it uses gasoline B?
-----------------------------------------
405/120 =3.375 ****************----> 405/72= 5.62
-------------------------
I can belive that my answer is 405/120! how can I get this terrible number 120?
you are right, again!

cook

thank for question 9. You know, I made a silly mistake, too. Be careful!!!!!!!!

qiufeng1990

1.DS有图。
说三角形ABC（逆时针）AB与X轴平行BC与Y轴平行。求B点横坐标。
1.A(-1,2)
2.C(8,10)
答案：B *************---> C
----------------------------
yes, you are right!???????   B不对？？？ BC//Y=>x(b)=8.

qiufeng1990

11.DS
一四边形KPMQ（逆时针方向），四边相等。求KM？
1.KP=2
2.PQ=2
答案：C **************-----> D
-----------------------------------------
You are right too. I forgot the condition 四边相等.

????四边相等.??? C!!!!!

tongxun

绝对的糊涂！四边相等只是个菱形而已，答案是C。只有正方形才能选D

qiufeng1990

还是认为16是C!!

tongxun

答案没改啊。

qiufeng1990

tongxun,

1.DS有图。
说三角形ABC（逆时针）AB与X轴平行BC与Y轴平行。求B点横坐标。
1.A(-1,2)
2.C(8,10)
答案：B *************---> C
----------------------------
yes, you are right!??????? B不对？？？ BC//Y=>x(b)=8.
为什模是C? B已胡了！

tongxun

qiufeng1990：我可不可以不脸红？

cook

Shamed.! 1.求B点横坐标。 but I thought B 点坐标
         16. PLease advise. How many is all the boys and girls in the class?
          How do you get numbers of girls in the class?
thanks your guys!