数学M/S Paper 2讨论专区

sim91

A farmer plants 3 types of durians,A,B and C in the ratio 5:3:2.The yield of large fruits among the types are 30% for A,40% for B and 60% for C.It found that squirrels eat 5% of types A durian,10% of type B durian and 20% of type C durian.

a)What is the proportion of large fruits produced in the farm?{ans:39%}
b)How many per cent of the large fruits are eaten by the squirrels?{ans:11.2%}
c)How many per cent of the fruits eaten by the squirrels are large?{ans:45.8%}
d)Is there any evidence to show that squirrels prefer smaller fruits?

各位帮帮忙啊 这题我做到(b)的答案不对 老师也说他找不到答案 可以教教我怎样找到答案嘛

walrein_lim88

A farmer plants 3 types of durians,A,B and C in the ratio 5:3:2.The yield of large fruits among the  ...
sim91 发表于 16-4-2010 06:03 PM

   

sim91

呵呵...35题要如何找weighted
http://img683.imageshack.us/img683/5284/img0002vd.jpg

walrein_lim88

回复 163# sim91


是24696..不是246916...

sim91

回复  sim91


是24696..不是246916...
walrein_lim88 发表于 2-5-2010 01:41 PM

谢谢你啊..原来是我用错formula了我想请教你36题到底在说些什么 有点confused啊

walrein_lim88

谢谢你啊..原来是我用错formula了我想请教你36题到底在说些什么 有点confused啊
sim91 发表于 7-5-2010 05:53 PM

问你：
如何选suitable base year
还有WEIGHTAGE的重要性
THEORY问题来的。。
（P/S:我不会答，我会算罢了）

harry_lim

这张纸的第三题我有点问题 找不到其中一个
sim91 发表于 24-3-2010 06:56 PM

gopeng是在霹靂州的吧???

sim91

回复 167# harry_lim


   对啦...

harry_lim

回复  harry_lim


   对啦...
sim91 发表于 9-5-2010 09:37 PM

什么學校的???

sim91

回复 169# harry_lim


   SMK SERI TEJA一间算蛮新的中六学校

harry_lim

回复  harry_lim


   SMK SERI TEJA一间算蛮新的中六学校
sim91 发表于 10-5-2010 04:09 PM

哦
數學怎樣???

sim91

回复 171# harry_lim


   还可以撑下去的只是对p1的题目觉得有点吃力 看不明白问什么
可能脑袋转不够快呱

harry_lim

回复  harry_lim


   还可以撑下去的只是对p1的题目觉得有点吃力 看不明白问什么
可 ...
sim91 发表于 11-5-2010 05:28 PM

幸好我的兩張paper的grade都是一樣

sim91

hmm..这个题目我只找到前面的答案后面的答案不对..想问问到底哪里做错了
3. For a set of 12 observations,∑x=43.2 and ∑y=56.4. The regression line of y on x goes through (1.6,2.5) and the regression line x on y goes through (4,6.2). Find the equations of the 2 lines.
[Ans：y=0.74-1.1x, x=7.09-1.65y]

walrein_lim88

hmm..这个题目我只找到前面的答案后面的答案不对..想问问到底哪里做错了
3. For a set of 12 observations,∑x=43.2 and ∑y=56.4. The regression line of y on x goes through (1.6,2.5) and the regression line x on y goes through (4,6.2). Find the equations of the 2 lines.
[Ans：y=0.74-1.1x, x=7.09-1.65y].
sim91 发表于 14-6-2010 06:33 PM

mean of x =43.2/12 =3.6 and mean of y =56.4/12 =4.7
regression coefficient of y on x = (4.7-2.5)/(3.6-1.6) =1.1
Equation of regression of y on x:
y - 4.7 = 1.1(x-3.6)
y - 4.7 =1.1x - 3.96
y =1.1x + 0.74

regression coefficient of x on y =(3.6-6.2)/(4.7-4)=-3.714
Equation of regression line of x on y:
x - 3.6 =-3.714(y - 4.7)
x = 21.0558 - 3.714y

yingchin

Solve the following linear programming problem by using simplex method.
Maximize : F = x+2y
3x+y(Smaller/equal to)15
3x+4y(Smaller/equal to)24
x(bigger/equal to)0
Y(Bigger/equal to)0

谢谢你们的帮助！！

walrein_lim88

Solve the following linear programming problem by using simplex method.
Maximize : F = x+2y
3x+y(S ...
yingchin 发表于 24-6-2010 09:26 PM

   

harry_lim

walrein_lim88 发表于 27-6-2010 03:50 PM

很怀念这题哦
虽然2009年没有出

walrein_lim88

很怀念这题哦
虽然2009年没有出
harry_lim 发表于 28-6-2010 11:42 AM

    。。。还记得你这题是考试前才问我的吗？

sim91

这题做到一半就卡住了..希望各位多多指教
The selling price and the assessed price of medium-cost houses in a certain area are summarized as follows:
mean assessed price=RM 46700
mean selling price=RM 50950
Standard deviation of assessed price=RM 37100
Standard deviation of selling price=RM 39900
Correlation coefficient between selling price and assessed price=0.998
A property agent expects that there is a linear correlation between the selling price Y and the assessed price X an given by the equation Y=a+bX.
i.Determine the values of a and b.Give your answers correct to 2 decimal places
ii.Draw the line of regression line of Y on X.Give a brief comment on your answer.
iii.By using the line of regression line drawn,determine the expected selling price of a house which is assessed to be worth RM 50 000.
iv.State whether the regression line can be used to estimate the selling price of low cost houses in a different area.Give reasons.