Your Probability Test

I have completed my marking of your Probability test.

I am very pleased and estatic to announce that there is a student in your class who scored full marks!

Nonetheless, there are a handful of failures.

However, from your answers, I can see that most of you understood the topic well.

P(selecting a student who do not understand the topic)=0.05
P(selecting a student who is very fluent with the topic)= 0.35

Common errors....

last question: Probability that XX passes driving test each month is 0.7.
a)What is the probability that he will pass in either the first or second month?
b)What is the probability that he will pass in the first 3 months?

a) P(1st or 2nd month)= P(1st month pass) + P(1st month fail, 2nd month pass)

b) P(1st 3 months) = a + P(1st month fail, 2nd month fail, 3rd month pass)

...if you pass in your first month, will you take it again the 2nd or 3rd month?

Similarly, the probability that the Guru buys this LV speedy in a particular month is 0.8.

What is the probability she will buy it in Jan?
What is the probability that she will buy it in Jan or Feb?
What is the probability that she will buy in in the first 3 months?

If I buy it in Jan, do you think I will buy the same bag again in Feb or the 3rd month?
No! I will buy something else....e.g.

You all get what I mean?

homework and things to bring 26/2/09

Todays hw:
a math tb exercise 19.2 qn 3b,4b,5b,7b do in a math 1
heymath weekend assignment...print or copy

friday's lessons:
mother tongue , A math , english , socials studies

REMEMBER!!!
bring along your A math tys and notebook just in case mdm lo ask for it...
buy your geography workbook (sec 3 , 4) by next geography lesson
sign and bring the green edusave form thing tomrrow

Error to Weekend HW Q2

....for your info, the HW is from Heymath!

homework and things to bring 25/2/09

Todays hw:
a math tb exercise 19.2 qn 1a,b,e,f, 2a,b,e,f do in class notebook
heymath weekend assignment...print or copy

thursday's lessons:
A math , geography , chemistry , english , socials studies

REMEMBER!!!
bring along your A math tys and notebook just in case mdm lo ask for it...

PROBABILITY JOURNAL WRITING---WINNER!!

The winner is............BJORN!

Here is his journal.

Q: One day, you saw your uncle queueing under teh hot sun to buy 4D/Toto. Explain to him why he should not waste his money on these. Use the concept of probability to explain why the lottery company will always win.



There are some other entries that are good too. Here are the excerpts from some other entries:

Ha's entry


Xue Chun's entry

DEFINITE INTEGRAL

My personal feelings about today's session:

There is collaboration amongst students. (which is good)
People are really questioning why and not just copying blindly.


Learning really takes place!

Just some AFIs (Area for Improvements)
-When you discuss/spar ideas, be mindful that there are otehrs around you. Hence, keep your conversations short and not so loud.
-Bring rough paper of your own so taht you can take down notes etc.

These are solutions to 2 questions for today's HW. For your ref JIC you are nto osure how to present your answer.

Q1a


Q2f

homework & things to bring 24/02/09

Today's homework:
E math 2, Ex 4.2 Qn 12, 13, 14
Phy WS
EL comprehension (those who haven finished)

Wednesday's lesson:
Phy, A math, Chem, MTL, ACT( Social Studies )

Remember tt you DON'T NEED to bring A math TYS & TB...
lesson will be held at computer lab 4!!
Secondly, remember to bring the GIRO form.

homework and things to bring 23/2/09

hi guys sorry for the wait......

Todays hw:
E math tb revision exercise 2 all question on foolscap paper
E math tb exercise 4.2 qn 1-4 do in textbook

tuesday's lessons:
PE , e math , physics , mother tongue , ME , English

REMEMBER!!!
bring along your E math tys and notebook just in case mdm lo ask for it...
louis chua remember to bring your edusave form tomrrow or ms liu will ask you to go home and get it
those international students that have not paid the $65.55 , please bring it tomrrow or ms liu will send u home to take it as well
bring all your olympics notes tomrrow so that you can put it in the file

p.s
u guys can use the science blog for science questions that u guys don't understand
me and ben will try to help u guys out ^^
i have bought the pe files for the class , i will bring it tomrrow during pe lesson

homework & things to bring 20/02/09

Homework on friday (20/02/09):
A math 2, Ex.19.1 Qn 3c,d,4,5,6.

Monday's lesson:
Assembly, English, E math, Geog, ACT(phy)

Remember to bring E math TYS in case Mdm Lo needs it...

As requested by Lucas:the sock question

Here is part of the tree diagram.



Clue: This question is a no-replacement question.

e.g. Find the probability that he takes 2 black socks.

That will be he get a black sock, then another black sock.
Hence P(B and B) = 2/10 x 1/9 = 1/45 (after he takes out 1 black, there is only 1 blakc left and a total of 9 socks.)

Hope this is helpful.

Qn 7 worksheet on probability

3 pairs of white socks, 2 pair of black socks and 5 pair of grey socks are mixed and put in a drawer. on a particular day, john woke up late. He randomly snatched two socks from the drawer, put them on and rushed to work.
(a)represent the sample space using a tree diagram
(b)find the probabilty that john has taken
(i) a pair of socks of the same colour,
(ii) a pair of socks of different colours,
(iii) a black sock and a white sock.

4N1 Rhapsody

Students, please hold your pen,
Put your pen against the paper,
write down all the formulas,

Students, lesson had just begun,
But some of you are already dreaming away-
Students ooo,
No matter what, you must try-
I will not repeat this again, tomorrow-
Carry on, carry on, you know every lesson matters-

Too late, exams have come,
Send shivers down your spine-
Your head's aching all the time,
Goodbye to your books and notes
Gotta leave them all behind and face the truth-
Student ooo-
you don't want to fail,
Don't you wish you had studied a little more?

---sung to the tune of Bohemian Rhapsody (By Queen*)

*NOt ShuWen, But Queen as in Freddy Mercury Queen

homework and things to bring 19/2/09

hi guys sorry for the wait......

Todays hw:
A math tys pg 110 , qn 10 , 11 ... page 111, qn 13 , 15 ... page 112 , qn 16
More practice on probability paper

friday's lessons:
mother tongue , a math , english , socials studies

REMEMBER!!!
bring along your A math tys and notebook just in case mdm lo ask for it....
those who haven give the edusave forms remember to bring it tomrrow

p.s
u guys can use the science blog for science questions that u guys don't understand
me and ben will try to help u guys out ^^
for the PE file , do u guys want to buy it yourself or u wan me to buy for u guys
its not free u have to pay... but it is cheaper i think...
comment on this post , but by friday if less then 7 person commented , u guys will have to buy it yourself

E Math Probability HW

These are tips for Ex 2.4 Q12-14

Q14
I will use a simpler example to explain.

I have forgotten my password to my hurray! account. I know it is either pretty123, gorgeous123 or enchanting123. I have two tries to get it right. So i type in "pretty123" but it is wrong. I am prompted to key in the password again. Which password should I key in now? HOw many choices have I left?

So the probability of me being successful in my 2nd try is
P(successful in 2nd try) = P(fail 1st try, successful 2nd try) = (1/3)(1/2) = 1/6

Q13
This is similar to our Mr. Pitt getting married and having a child with blue eyes question.

Q12
Draw a tree diagram.

VECTORS E LEARN

THIS IS THE DIAGRAM FOR STEP 6.

Tips to A Math TYS questions

p. 112 Q16a

Find the x coordinate of the point on the line y= 5 - 2x where xy is a maximum.

How to think in this question?
Firstly, we usually do dy/dx and we need to have a y function in terms of x e.g. y=ax+bx^4.
In this question, there is no direct function of x. However, you are given y= 5 - 2x and xy. Can you put them together?

i.e. substitute y= 5 - 2x into xy?
Then you differentiate the function w.r.t x.
To find max or min, the 1st derivative =0.

p. 110 Q11
Some of you asked me what is a flower bed?
In this IT age, you can utilize the wonderful internet and just GOOGLE it!

Jay Chou sang about a chrysanthemum flower bed -- 菊花台
You can also see the link here for FLOWER BED

The important thing here is to sketch a simple diagram based on the requirements of the question.

And the diagram is VERY simple! Only a circle and a square!
However, there may be different ways to draw them.

No matter how you lay these two flower beds, your fence will be the perimeters of these two shapes. Hence, x(x) + circumference of circle = 40 (total lengthof fence as given by the question). You can then express x in terms of r and pi.

homework and things to bring 17/2/09

hi guys sorry for the wait......

Todays hw:
A math tys pg 110 , qn 10 , 11 ... page 111, qn 13 , 15 ... page 112 , qn 16

tuesday's lessons:
physics , E math , chemistry , mother tongue

REMEMBER!!!
bring along your E math tys and notebook just in case mdm lo ask for it....
those who haven give the edusave forms remember to bring it tomrrow
the A math hw is due on friday and not tomrrow so take your time to do it...
the E math homework is due tommrrow remember to do it ^^

p.s
u guys can use the science blog for science questions that u guys don't understand
me and ben will try to help u guys out ^^

home work and things to bring 16/2/09

hi guys sorry for the wait......

Todays hw:
E math tb exercise 2.4 qn 5 , 7 - 14

tuesday's lessons:
PE , a math , physics , mother tongue , ME , english(act)

REMEMBER!!!
bring along your A math tys and notebook just in case mdm lo ask for it....
those who haven give the edusave forms remember to bring it tomrrow
the E math hw is due on wednesday and not tomrrow so take your time to do it...

p.s
u guys can use the science blog for science questions that u guys don't understand
me and ben will try to help u guys out ^^

Our weekly plan.

Tue A Math
1. going through Block test corrections
2. reflections
3. Math weekend HW

Wed E Math
1. E learning (Introduction to Vectors)
2. Online test on Probability

Thu A Math
1. Introduction to Integration ch 19

Thu ACT
1. E Math--Statistics and Probability

Fri A Math
1. More on Integration ch19

Preview of Next week:
Class test on Probability
Class test on Differentiation (More focus on Connected rate of change and Maxima and MInima)

homework and things to bring 13/2/09

hi guys sorry for the wait......

Todays hw:
practice exercise part 3 qn 1 , 3 , 4 , 8-11

monday's lessons:
english , E math , geography , chemistry(act)

REMEMBER!!!
bring along your E math tys and notebook just in case mdm lo ask for it....
those who haven give the edusave forms remember to bring it tomrrow
tomrrows act should be chemistry because last week monday is the physics test

p.s
u guys can use the science blog for science questions that u guys don't understand
me and ben will try to help u guys out ^^
i will ask ben to put a chat box asap in the science blog ^^

Tips to A Math weekend assignment

Dear 4N1, here are tips to this weekend's A math assignment on Maxima and Minima.

Q1 Very simple. I am sure you can do it!

Q3 Also very easy.

Q4 Just find turning point and use the 2nd derivative to determine whether it is max or min.

Q8 Don't you think this resembles the question we discuss in class on Fri, when I cut out a piece of blue paper to illustrate the question? Well, you can draw out this diagram too, to help you understand. Remember, you need to find the volume too.

Q9. wait for my upload

Tips to today's HW

Q6
Volume of a cuboid = L x B x H
In the question, can you see that x+y=3 (as 2x+2y=6)

For the base of the box, one side is y, the other side is 2-2x.

Hence, for the cuboid,
you have
L : y or (3-x) because x+y=3
B : 2-2x
H : x

Hence use L x B x H to find vol of box.

For this topic, instead of dealing with y=function of x all the time, we solve problems relating volume of prisms, areas etc.

Method is similar to finding turning (stationary points) of curves.
Tomorrow I will still spend some time on this topic.

homework and things to bring 12/2/09

Todays hw:
exercise 16.3 do in a math notebook qn : 1a , 1c , 2a , 2c , 6

wednesday's lessons:
mother tongue , a math , english , socials studies

REMEMBER!!!
bring along your a math tys and notebook just in case mdm lo ask for it....
those who haven give the edusave forms remember to bring it tomrrow

On discussion of class t shirts.

Erh... like what I told some of you, this blog is meant for the discussion of Mathematics.

However, since the level of enthusiasm is so high, I will temporarily allow the discussion of Class T shirts here.

Nonetheless, I would like to impose some conditions.

1. For any poll/voting, you must do a statistical report. (measures of central tendency, pie chart etc)

2. For collection of money for the t shirts, a spreadsheet (for accounting purpose) must be posted here.

3. Do not comment using a new post! Keep the blog neat and tidy. If you need to comment, click on post a comment.

4. Every post must have a title and a label. Label should be Class T shirt. Examples of titles can be "Class T shirt Design 1", "Payment for Class T shirt" etc.

class tee

4n1 plz visit my blog to vote for the colours of class tee shrt

homework and things to bring 11/2/09

Todays hw:
exercise 16.2 do in a math 1 qn : 1a , 1d , 2a , 2d , 3-9

wednesday's lessons:
a math , geography , chemistry , english , socials studies

REMEMBER!!!
bring along your a math tys and notebook just in case mdm lo ask for it....
and good luck for the a math test tomrrow^^
remember to sign your edusave form for the local students and bring the money for the international students

class T-shirt

most of u guys wan to make a class T-shirt for our class
so i need ppl to come up with designs and post it on the blog
and wad colour u all like, our friend wu pan will check out the prices for us

things to bring and homework 10/2/09

Todays hw:
exercise 2.3 qn 1~6 , do in math 2

wednesday's lessons:
physics , a math , chemistry and mother tongue

REMEMBER!!!
bring along your a math tys and notebook just in case mdm lo ask for it....
and good luck for the geography test tomrrow^^
remember to bring physics stuff for physics lesson
set square
protractor
workbook
textbook
file

Online test for Probability

Those who did not have MT Block test attempted this online test on Probability.
Heymath online test on Probability


Despite informing them and reminding them about responsibility in learning and integrity, some were discussing the solutions and helping one another.

This is a self test for you to find out whether you really understand the topic of Probability. This is a matter of self awareness. When you do the test and find that there are certain questions which you do not understand, you can read up on it or post your queries here. There is absolutely no point getting full marks from sharing solutions with your friend.

Hence, I will expect all of you to complete the online test on your own! THIS IS A SELF TEST! Deadline: 11pm on Sunday (15 Feb)

Some resources

A website you can access to know more about Probability, especially those who think you need more explanations.



http://www.mathgoodies.com/lessons/vol6/intro_probability.html

JOURNAL WRITING 09/02/09

I had a glimpse of some of the Journal Writing you all did during my absence.

A few were quite good written.

Nonetheless, some did not read the question correctly.

You are supposed to write a letter.....

Anyway, I will be giving out prizes to the top 5 articles.

hw and things to bring 9/2/09

Todays hw:
exercise 2.2 qn 5-13

tuesday's lessons:
PE , E math , physics , mother tongue and ME

REMEMBER!!!
bring along your e math tys and notebook just in case mdm lo ask for it....
and good luck for the mother tongue test tomrrow^^
remember to wear pe shirts and shorts tomrrow... u don't wan to do extra push ups...

Some help regarding connected rate of change

En ze commented that he has difficulty in sieving out the important information in connected rate of change questions. I am sure many otehrs face the same problems too.
So, I am going to post this 2 examples to illustrate how you can sieve out information.






The types of questions are endless. These are but 2 out of the tonnes that I have.
Nonetheless, with the right attitude and adequate practice, all of you shouldbe able to do these questions in future.

HEY ben!! wow nice blog... but thanks for the solution. it really help me... the kopitiam prank is funny!!!!!1 see u at school!!!!!!!!!!!!

Clues to your HW Ex 16.1

Q1-3 are very standard questions. You are should not have problems.

Q4. A similar question was done in class. Check your class ntoebook.

Q5a. Find dy/dx. (you should know what rule to use)
Q5b. At stauionary points, dy/dx = ? (hence you can solve to find x)

Q6.
Just do your dy/dx first.
Then, ask yourself: What is the dy/dx at the stationary point?
Since the stationary point is at (3, 5), the value of x is 3.
Substitute into dy/dx and you get 1 linear eqn.
At this point, x=3 and y=5. Substitute into original equation and you should get another linear eqn.
Solve simultaneously.

Q7 to 10 are quite similar.
All of you should be able to do dy/dx and find the x-coordinates of the stationary points.
What does nature of the stationary points mean?
Whether they are minimum, maximum or point of inflexion. (check textbook examples)

HOMEWORK AND THINGS TO BRING 6/2/09

hey guys sorry for the late post if ppl even see my post....

Todays hw:
A math textbook ex 16.1 all the questions, do on foolscap paper
geography paper on rivers ( do it if u don't want to stay back with mr john lim...)

monday's lessons:
english , E math , geography

REMEMBER!!!
bring along your e math tys and notebook just in case mdm lo ask for it....
and good luck for the physics test on monday ^^ hope many ppl can win me this time because i don't want to send my files for checking haha

p.s
remember to check out the post below mine ^^

homework tips out in sc1enceguru.blogspot.com by your science guru ben pang lol...

A Math HW, E Math common test

It is so difficult to try to contain my laughter in class.
My face was stern but my heart was smiling.
Very nice to see the class so co-operative, quiet and attentive.
Should we keep up with this? Tell me by commenting below.


Anyway, this weekend's A math assignment should be done on foolscap paper. You can do several questions on 1 page. However, you must be neat and clear.

Try all questions first. I will post some clues here on Sunday.


E Math common test--
Generally, I am happy with the class' performance.
I will give out the paper on Monday and we will do corrections then.

A maths home work clues for 5(ii)

use the formula dv/dt=dv/dx. dx/dt
dv/dt = 40
dv/dx=pie height square/9
find dx/dt

the depth x means height so all height are convert to x

Q5 clues

typo error in question.............

replace r by x.

Solutions for Amath homework, specially by CHARLENE TAY!!! :) :) :)

Q1. y=(3x-2)^10 over 6

dy/dx = 10(3x-2)^9 (3) over 6

= 30 (3x-2)^9 over 6

When x=1/3,

30 (1-2)^9 over 6 = -5

dy/dx = dy/dx . dx/dt

dy/dx = -10 units/s

Q2.

(i) Clue-Write down all the information given first then start thinking.

dv/dt = dy/dx . dx/dt

60 = (0.03x^2 + 4.4x + 200) . dx/dt

When x = 10, 60 = (3+44+200) . dx/dt

60 = 247 . dx/dt

dx/dt = 60 over 247 cm/s

(ii) dx/dt = 0.2

60 = (0.03x^2 + 4.4x +200) . 0.2

0.03x^2 + 4.4x - 100 = 0

Use formula to solve for x.

Ans: x = 20cm

Q3. y = 3/4 ( x/12 - 1)^6

dy/dx = 3/4 [(6) (x/12 -1)^5 (1/12)]

= 3/8 (x/12 - 1)^5

dy/dt = 12 dx/dt

3/8 (x/12 -1)^5 = 12

(x/12 - 1)^5 = 32

x/12 - 1 = 2

x/12 = 3

x = 36

y = 3/4 ( 36/12 - 1 )^6

y = 48

As for Q5, we'll ask Math Guru tomorrow in class.

(cause I also don't know how to do , hahahas :p) but do try, if not she will scold! >:{

4N1, jia you! Study hard! Don't make our teachers DISAPPOINTED!

05Feb TYS homework.

05 feb TYS HW

Topic: Differentiation--Rate of change

TYS unit 11b p. 104-106
Q1 is a basic question which everyone should be able to complete!
Q2 has been discussed i nyour weekend assignment. Hope you still remember!
Q3 Similar to your HW from ME15.
Q4 Not in your syllabus. NO need to complete.
Q5 Similar to example 3 in your TYS (p.104)
Q6 NOt in your syllabus. NO need to complete.

I will collect your HW during flag raising. Please be ready with your HW in your hand.

THERE WILL BE CONSEQUENCES FOR BEING NOT SERIOUS IN YOUR WORK AND NOT RESPONSIBLE FOR YOUR OWN LEARNING!
YOU REAP WHAT YOU SOW!

homework and things to bring 5/2/09

Todays hw:
A math tys differentiation - rate of change all questions except those that mdm lo pointed out at the next post

geography paper on rivers

Tomrrows lessons:
mother tongue , a math , english , socials studies

REMEMBER!!!
the A math tys hw will be collected during flag raising so complete it at home don't wait until the next day to do it in school..

p.s
to mdm lo... the disappoint thing is a typo error.. i forgot the don't behind...

Your weekend homework.

I know some of you have problems with your weekend HW.

So, I will offer some help here:

E Math

TYS Q10b. You must find out what is the number of litres of oil left after leak.
ans: (500/x)-3.
The cost of the paraffin is now $x+1.
Hence, to calculate the money he received from selling the paraffin, you must multiply (500/x)-3 by x+1. (hint: Make it a single fraction)

A Math worksheet

Q2 Ht of cylinder is thrice its radius.


Q4


Hope you find the above clues helpful.