Sir Cloudy Tutorial

m5b10 assignment | locus & simple constructions

2010-07-20T20:06:00.000-07:00

Here is your next assignment.
Note: do them on piece of plain paper. each question on a fresh page of paper.

http://dl.dropbox.com/u/8515507/assignments/locus%20assignment.pdf

due : 26/7/2010

m5b10 assignment 5 | misc problems

2010-07-11T07:28:00.000-07:00

here is another assignment for you. download it and answer all questions.

as for the due date, this time i will let you relax a little bit...just a little bit though. dateline : 21st July 2010

http://dl.dropbox.com/u/8515507/assignments/men%205b%20assignment%205.pdf

m5b10 assignment | sets & venn diagram

2010-07-03T18:38:00.000-07:00

here is another assignment on the topic of sets & venn diagram. as usual, the dateline is one week i.e. 12th july 2010

http://dl.dropbox.com/u/8515507/Sets%20%26%20Venn%20Diagram%20assignment.pdf

since your book is with me, do this on a piece of paper and submit to me. do the pasting later. any question, just tweet me

M5B10 assignment

2010-06-27T05:34:00.000-07:00

It's been a long time since I've assigned another assignment. So, here it is, assignment on probability. Just in case you have a problem opening it, please see me ASAP. Due date will be 5th July 2010.

http://dl.dropbox.com/u/8515507/PROBABILITY%20ASSIGNMENT.docx

Instruction: As usual, paste this paper inside your assignment book and answer all.

M410 CLASSWORK

2010-02-02T04:38:00.000-08:00

TOPIC : VARIATIONS

http://rapidshare.com/files/344792332/variations_exercises.pdf

HOW TO DOWNLOAD FILE?

2010-01-20T07:23:00.001-08:00

okay, now here is the step-by-step.

1. copy the address that I have given e.g. http://rapidshare.com/blablablae/etc

2. paste that address into the address box of your browser, then enter. you will be directed to rapidshare.com page.

3. click on the free user button (the left ones)

4. you will be prompted to wait for several seconds (i don't remember how long, 60 seconds maybe)

5. after the countdown has finished, you will be presented with the DOWNLOAD button. press it then.

6. don't worry, most of my files are very small, so it will take very little time to download.

M410 ASSIGNMENT 1

2010-01-19T15:58:00.000-08:00

Download the assignment paper from the link below.

Do show your workings and answer on the paper itself.

Please be as neat as possible.

If your workings is done on another piece of paper, fasten and submit them too.

Due date is on 23/1/2010.

Any assignment submitted after this date will not be entertained.

If you have any problem downloading, please ask me.

http://rapidshare.com/files/240600186/Solving_Quadratic_Factoring.pdf

men 4B assignment 7

2009-08-24T18:59:00.000-07:00

topic : graphing straight line on Coordinate Geometry

link : http://rapidshare.com/files/271123792/asg_7_graphing_straight_lines.PDF

due : 1st september 2009

men 3 assignment

2009-08-03T19:28:00.000-07:00

topic : standard form

http://rapidshare.com/files/263456303/men_3_asg_-_standard_form.PDF

do ALL questions. This is also part of your revision for the big exam. try your best (and honestly) to do it without the aid of calculator

due : before 13th August 2009

men 4B assignment 6

2009-08-03T19:25:00.000-07:00

topic : operations on matrices

link : http://rapidshare.com/files/263456214/asg_6_matrices_operations.PDF

as usual, paste it into your assignment book. Do ALL questions.

due date : 11th August 2009

men 4B : assignment 5

2009-07-10T19:11:00.000-07:00

topic : simultaneous equations

link : http://rapidshare.com/files/254403091/asg_5_simultaneous_equations_by_elimination.PDF

due : before 20th july 2009

MEN 4B 09 CW

2009-06-03T22:02:00.000-07:00

TOPIC : QUADRATIC EQUATION

INSTRUCTION : DOWNLOAD, PASTE IT INTO CLASSWORK 1 BOOK, AND ANSWER ALL QUESTIONS.

LINK : http://rapidshare.com/files/240600186/Solving_Quadratic_Factoring.pdf

ANNOUNCEMENT TO MY CURRENT STUDENTS 4B, 3R & 3Y

2009-06-03T09:39:00.001-07:00

Due to some strong request, I have to give some additional works to you. And also since MOE has blocked the access to the blogging site at school, so I am expect your cooperations in finding way(s) to download the works i've uploaded here.

choices are
- download from home
- photocopy the works from friends who have downloaded the file
- get the works directly from me via pendrive, thumbdrive, etc.

MENENGAH 4B MATH ASSIGNMENT 4

2009-06-03T09:35:00.001-07:00

A straight line, of gradient 3, passes through the point (0, 7). Write down the equation of this line. A second line, drawn parallel to the first line, passes through the point (3, -2). State the equation of this second line. [3]
(a) Find the gradient of the straight line through the points (2, -2) and (7, 8). [2]
(b) Find the equation of the straight line which passes through (3, 5) and has gradient - 4. [2]
Given that x ≤ 12 ¼, state the largest possible value of x if
1. x is an integer, [1]
2. x is a prime number, [1]
3. x is a rational number. [1]

due date : saturday 6th june 09

MEN 4B 09 : MID YEAR EXAM PREPARATIONS

2009-04-19T19:59:00.001-07:00

All right girls. Here I post another question papers, again as part of your preparation for the mid year examination. I prefer for you to download them by using the link since I want to make this very exclusive just for Men 4B girls. So download them now, print, try them and let see what's your progress. Please, ask me questions okay. I will update and add another link from time to time, so keep visiting this space.

click here

Men 4B : classwork

2009-04-14T19:21:00.001-07:00

As part of preparation for the mid year examination, here I prepared some questions on the topic stated below. Print these questions so that we can discuss the solutions in the next lesson. If you want to try them first, you are most welcomed and also, if you have any question on that, please do approach me. I will prepare some more questions for the other topics, Insya-Allah since I want you girls to produce an outstanding results.

ARITHMETIC PROBLEMS, SIMPLE FINANCIAL TRANSACTIONS, PROFIT AND LOSS, SIMPLE INTEREST

Examples

In a shop, a bicycle is priced at $451. The price includes Government Tax at 10%. How much is the tax?
Apples cost 12 cents each. John has a $5 note and wishes to buy as many apples as possible. Calculate
- The number of apples that he can buy
- The change that he will receive.
Calculate the simple interest when Rs330 is invested for 8 months at 7% per annum.
A shopkeeper sold a book for Rs180. He made a profit of 20%. Calculate the cost price of the book.
The exchange rate between the European Euro (€) and the American dollar ($) during one summer was €1 to $1.60.
- How many dollars would an Englishman get for €400?
- How many Euro would an American get for $800?
The owner of a toyshop made a profit of 40% on every toy which he sold.
- Find the selling price of a football which cost the shopkeeper $11.
- Find the cost price of a doll which the shopkeeper sold for $28
- The shopkeeper made a profit of $10 when he sold a kite. Calculate the selling price of the kite.

Exercises (no calculator is allowed in answering any part of these questions)

A bank charges $28 simple interest on a sum of money which is borrowed for four months. Given that the rate of interest is 15% per annum, calculate the sum of money.
Find the cost of 24 football jerseys which cost $6.70 each.
The total cost of a car service consists of a basic price plus a tax of 15%. Given that the total cost is $69, calculate the basic price of the service.
A bank exchanges French currency for Bruneian currency at the rate of 11 francs to the BND.
- Calculate, in francs, the amount received in exchange for BND12.50
- Calculate, to the nearest cents, the amount received in exchange for 80 francs.
A man earning BND5625 per annum is awarded a pay rise of 8%. Calculate his new annual salary.
The cost of 15 identical textbooks is BND21.30. Calculate the cost of 1 book.
A sum of BND350 is invested at simple interest and amounts to BND476 after 3 years. Calculate
- The total interest,
- The rate per cent per annum
In a sale, all prices are reduced by 40%. Calculate the original price of an article whose sale price is $48.
- A man bought a picture for BND325 and sold it at a profit of 12%. Calculate the selling price.
- A dealer made a profit of 20% by selling a car for BND630. Calculate the price he paid for the car.
- Find the change from $5 after buying 28 pencils at 15c each.
- An aircraft arrives at its destination at 01 07 after a flight lasting 2 hours 23 minutes. Find the time at which the aircraft started its journey.
A car uses petrol at an average rate of 7.5 liters per 100 km. The owner spends BND20 on petrol costing 80c per liter. Calculate, correct to the nearest kilometer, the distance his car will travel on the amount of petrol.
Find the simple interest obtained when BND125 is invested at 8% for a period of 8 months.
- A lady buys an article marked at BND6.40 but, in addition, has to pay 15% tax. Calculate the total amount that she has to pay.
- When a shopkeeper sells a camera for BND84, he makes a profit of 12%. Calculate the cost price of the camera.
In a sale, a shop reduced all its prices by 20%. Calculate
- The cost of an article which was originally priced at BND26,
- The original price of an article which was sold in the sale for BND44.

for better printable version, you can download the pdf here.

Source : O-Level Classified Maths past year book.

Pythagoras Theorem CW for Men 3 (update)

2009-04-03T20:03:00.000-07:00

since some of the drawings are in 3d, i've decided to give it in printouts. download this file and do all workings and answers in the paper itself. no need to stick them in the book.

due wednesday, 8th april 2009

MEN 4B 09 : assignment 3

2009-03-30T19:24:00.000-07:00

http://rapidshare.com/files/215569768/stats.rar

right, download this file straight away, and do all the workings and answers on the paper itself. do not stick them into your book at the moment. once you're done, just submit the papers.

due date will be before 7th april 2009.

MEN 4B 09 : ASSIGNMENT 2

2009-02-10T18:27:00.001-08:00

Download the document.

http://rapidshare.com/files/196625222/MEN_4B_09_ASSIGNMENT_2.pdf

DUE DATE FOR THIS ASSIGNMENT IS TUESDAY, 17^TH FEBRUARY 2009 BEFORE 1230h. ANY QUESTION? DON'T HESITATE TO APPROACH ME.

MEN 3 ASSIGNMENT 2 : CARTESIAN GRAPHS [update]

2009-01-31T19:05:00.001-08:00

Draw the graph of 3x + y = 6, using the scale of 2 cm to 1 unit on both axes. Fill in the value table below to assist you.

x	-2	-1	0	1	2
y

Due date : 11^th February 2009, before 1230 pm.

UPDATE: first of all, my apology. it seems that there is a slight mistake in the value table. just ignore the 3 and -3. so here, the update values for x are only from -2 to 2. big thanx to Maihara (3R) for pointing out this problem to me.

reminder to all students

2009-01-11T20:38:00.000-08:00

this reminder goes to all of my men 3 and 4 students. do not mistakenly download the wrong file. check the posting date, and to make it much more specific, I purposely make the headings for each posting very obvious.

for menengah 4B, the title would be in this format:
MEN 4B 09 : (assignment/classwork)

for both of my menengah 3, the title format would be:
MEN 3 : (assignment/classwork)

MEN 4B 09 : assignment 1

2009-01-11T20:22:00.000-08:00

http://rapidshare.com/files/182309951/FORM_2_REVISION.pdf

copy the link into your browser then download them. print them.

paste them into your assignment book.

do all of the questions, showing all your working clearly.

due date will be on or before 27th January 2009.

works submitted later than that will not be entertained.

any question, please ask me personally or drop them in the message box.

MEN 3 : symmetry properties of solid notes

2009-01-11T20:12:00.000-08:00

here are the notes handouts on the topic above, goes specifically for both of my menengah 3 students.

algebra program for students

2009-01-11T00:56:00.000-08:00

here is an algebra program to aid students to understand math better. it is very simple and even showed step by step solution. grab it now!

http://rapidshare.com/files/182006523/P._Algebrator_4.0.1_by_yd.rar

Men 3 assignment 1

2009-01-10T23:43:00.001-08:00

this assignment goes to both of my menengah 3 students batch 2009. please save this file, print them, stick them into your assignment book, do them all and submit. read the instructions carefully. the due date for this assignment will be before or on Saturday, 17th January 2009. any assignments submitted later than that will not be entertained (whatever excuse given will be considered invalid).

2009 another new season

2009-01-07T05:12:00.000-08:00

this year, i will try to make good use of this blog to post my assignment for the students. whereas for the notes and the classworks, i will think of something else, might be another blog or the oncoming school's official website. by the way, for all my students, all the best and let the "game" begins!

Happy Teachers' Day

2008-10-18T07:05:00.000-07:00

today, some people got their special holiday, since today is the Teacher's Day! kepada semua insan-insan yang bergelar guru, tak kira guru ugama kah, melayu kah, inggeris, guru terlatih, pegawai pelajaran, mana saja tah...dengan ikhlas diucapkan Selamat Hari Guru, semoga apa yang kita lakukan, kita lakukan kerana Allah, dan demi melihat negara dan tunas bangsa maju dan berjaya, didunia dan akhirat.

small mistake that leads to BIG mistake

2008-09-23T07:02:00.000-07:00

not really to point out the mistakes done by students, rather to correct the mistakes that can be prevented in math.

say, if the teacher asked as simple question (on formula) such as "what is the formula to find the area of triangle?", most students would reply "half times base times height". from this, the students will then write down in their paper as 1/2 x base x height. for me, I would say that this is very incorrect. why? read on, and you will be glad that you read. this is based on real situations and discussions.

Question: A triangle has a base of 10 cm. Given that its area is 20 squared cm, calculate the height of the triangle.

Common replies/mistakes done by students:
1/2 x base x height [a]
= 1/2 x 10 x 20 [b]
= 100 cm. [c]

ok. i am not making this up. the question is given to my year 11 (form 5) students, about 2 years ago when I was doing part-time tutoring. this question is so simple that I was very confident, all 10 students in that class would get it correct. it turned out that I was WRONG! Seeing this working (as shown above), I straight away spot the mistake.

Yes they got the idea right, the question is about area of triangle, which is shown in the line [a] that they have written. HOWEVER, they made mistake in writing down the formula. I always said this to my students, "WHEN YOU ARE WRITING ANY FORMULA, WHETHER IT IS SIMPLE, SHORT OR WHATEVER IT IS, MAKE SURE YOU WRITE DOWN THE COMPLETE FORMULA!"

Back to line [a]. for me, 1/2 x base x height is meaningless. I mean, what is 1/2 x base x height? Is it a formula? I would say no, since it does not have any indication or label. It is an improper way of writing down the formula. Because of this, students would mix up the information given by the question into their own version of the formula, as shown in line [b]. this student know the value for the base (10 cm) but when it comes to the value of height, this student got confused/lost. He/she might think "what is the height?? I am supposed to find the height, but where do I put this 20 cm in this formula?" Due to this confusion, the student then bet on their luck and put the 20 cm under the height space. See what I mean?

BETTER VERSION. If and only if, the student write down the complete formula, then it is almost impossible to make the mistake mentioned above.

Area of triangle = 1/2 x base x height

To make things simple, just remember this. Take formula as a puzzle, where you need to fill in as many empty spaces according to the clue given just to solve the question. In this question, we know the area of triangle (as given in the question) is 20 squared cm, so we fill 20 in the area of triangle space.

20 squared cm = 1/2 x base x height

Then, read again the question for the next clue. Do we know the value of base? Sure we do! It is 10 cm. Again, fill in the base space with 10 cm, to get

20 cm2 = 1/2 x 10 cm x height

From this, we are left with height. We don't have any value left to be picked from the question. Moreover, we are asked to find the height, so this is the complete set already. solve this!

20 = 1/2 x 10 x height
20 = 5 x height
20/5 = height
4 = height

From this discussion, what I am trying to emphasize is the importance of writing down the complete formula in solving math. Believe me, you won't regret it if you do what I suggest here. Because, formula are meant to be written in complete set so that you won't get mixed up or lost when solving them. GOOD LUCK!

a very useful math program for students

2008-09-01T08:09:00.000-07:00

while browsing around the internet looking for teaching materials, i came across this advert. i thought it was another of that spam thing. however, since the advert was very convincing (it even dare to give a full warranty of its originality), i tried my luck to click on it, only to find out that it IS for real.

this program is very small (the portable version), only eating around 6 mb of your computer's memory. i really recommend this program to all students since it is very useful, simple and student-friendly. it will help you to understand math better since it provides all the steps in solving math, especially algebra. the best thing is, it covers math and also additional math (such as differentiation, integration). so to students, grab this file now.

http://rapidshare.com/files/141817603/P._Algebrator_4.0.1_by_yd.rar

math brainteaser

2008-08-11T07:43:00.000-07:00

was browsing through my last year's postings in my blog, and i came across this math brainteaser. hehe...very good question. seems very hard, challenging, however when you got the answer, you will be like "laaa..."

You are on your way to visit your auntie, who lives at the end of the valley. It's her birthday, and you want to give her the cakes you've made.

Between your house and her house, you have to cross 7 bridges, and as it goes in the land of make believe, there is a troll under every bridge! Each troll, quite rightly, insists that you pay a troll toll. Before you can cross their bridge, you have to give them half of the cakes you are carrying, but as they are kind trolls, they each give you back a single cake.

How many cakes do you have to leave home with to make sure that you arrive at auntie's with exactly 2 cakes?

your answer? post them in the message board.

assignment for 4B (updated with answers)

2008-07-31T07:00:00.000-07:00

1. The sides of a rectangle are given as x cm and y cm, where

17.5 ≤ x ≤ 18.5 and 11 ≤ y ≤ 12.

Calculate

(i) The smallest possible value of the perimeter of the rectangle,

(ii) The largest possible value of the area of the rectangle

2. A restaurant owner pays a waiter an amount of $A per week. The amount is made up of a basic wage of $ 60 plus 11 cents for each of the n customers he serves.

The formula connecting A and n in this case is

A = 60 + 11n/100

(i) Calculate the amount of money the waiter received in a week when he served 240 customers. [ans : $86.40]

(ii) At the end of another week, the waiter received $ 115. How many customers did he serve? [ans : 500]

(iii) The owner of the restaurant decides to decrease the waiter’s basic wage to $ 45 but to increase the pay per customers to 17 cents. Write down the new formula connecting A and n. [ans : A = 45 + 17n/100]

(iv) Find the number of customers the waiter would have to serve in a week for him to receive the same amount of money whichever formula is used. [ans = 250]

2008-06-12T01:18:00.001-07:00

classwork (TIME)

2008-05-29T00:35:00.000-07:00

2. (a) A late night radio programme began at 2245 one evening and finished at 0320 on the following morning. For how many minutes did the programme last?

(b) A small bird enters its nest on average every 40 seconds, when it is feeding its young. How many visits to the nest does the bird make, on average, each hour?

6. (a) An overnight train left Singapore at 2240 and reached Kuala Lumpur at 0515 on the following day. How long did the journey take? Give your answer in hours and minutes.

(b) A worker in an electronics factory can complete one circuit panel in 3 minutes 25 seconds. Assuming that he continues to work at the same rate, calculate how long it will take him to complete ten identical circuit panels. Give your answer in minutes and seconds.

10. (a) Calculate the number of minutes there are in a day.

(b) (i) An aircraft was due to take off from Hong Kong at 1645. Because of bad weather it did not take off until 2110. For how long, in hours and minutes, was it delayed?

(ii) The aircraft developed a fault and returned to Hong Kong after a flight lasting 5 hours 25 minutes. At what time the next morning did it land?

14. (a) Calculate the number of minutes between noon and midnight.

(b) (i) An aircraft was due to take off from Singapore at 1740. Because of the bad weather it did not take off until 2215. For how long, in hours and minutes, was it delayed?

(ii) The aircraft developed a fault and returned to Singapore after a flight lasting 4 hours 10 minutes. At what time the next morning did it land?

17. (a) (i) A television programme lasted for 1 hour 25 minutes. The programme started at 09 40. At what time did it finish?

(ii) This programme was one of a serried of 5 programmes each of which lasted for 1 hour 25 minutes. How long did the 5 programmes last together?

(b) Another television programme lasted for 2 hours 12 minutes and finished at 0145. At what time did the programme start?

23. The diagram shows a timetable, part of which has been torn away, for trains from Manchester to London.

Manchester (depart) London (arrive)

08 35 11 25

12 31 15 19

17 15 20

22 37

(a) How many minutes does the train which departs at 1231 take to reach London?

(b) The 2237 train takes 2 hours 45 minutes to reach London. At what time does it arrive?

year 10 assignment

2008-05-29T00:30:00.000-07:00

Mr Edwards, Mr Jones and Mr Parry each decided to buy a new car which was priced in the showroom at $ 7200.

(a) Mr Edwards offered his old car in part exchange and the salesman allowed him $ 5850 towards the cost of the new car. Calculate how much more Mr Edwards had to pay for his new car. [ans : $ 1350]

(b) Mr Jones paid for his new car in cash and was given a discount. Given that he paid $ 6120 for his new car, calculate the percentage discount he received. [ans : 15%]

(c) Mr Parry agreed to pay 40% of the showroom price of the car as a deposit and the balance in equal monthly instalments over a period of 2 years. Calculate the amount of each monthly instalments. [ans : $ 180]

(d) The salesman had hoped to sell each new car for $ 7200 so that he could make a profit of 20% on the cost price. Calculate the cost price of each new car. [ans : $ 6000]

Hints

(a) Mr Edwards was virtually paying the new car with his old car. The salesman agreed, but said that his old car only worth $ 5850. So, Mr Edwards need to pay the remainder, but by how much? (very easy question).

(b) The discounted price of the new car is $ 6120. So, how much is the discount? Use the “before after” method.

(c) First, find 40% of $7200.

Secondly, deduct your answer from $7200.

Lastly, this remainder is to be divided by the no. of months in 2 years. (of course you know how many months)

(d) We are looking for the original price here.

connections between fractions and decimals

2008-04-28T21:54:00.000-07:00

do you know that, SOMETIMES when we have a problem in fractions, it is a good idea to try to change it into decimals to make things easier? also, if we have problem doing decimals, we could make things easier by changing it into fractions? yes, they are really connected, or in other words, interchangeable.

say, 1/2 + 1/4, how do you approach this question? we need the HCF of the denominator, etc...
hey, what if we change them into decimals? 1/2 is 0.5 and 1/4 is 0.25, so the answer is 0.75. wahh...so quick, isn't it?

in order to do this properly and efficiently, you need to have a very good number sense. say, 1/2 is half, so half of a number is 0.5 (everyone knows that). a quarter, 1/4 is 0.25, three-quarter, 3/4 is 0.75 etc. yes, a lot of them to be memorized. however, it makes life easier. really... here i list down some of the decimals that could be crucial in ANY calculations.

1/2 = 0.5
1/4 = 0.25
3/4 = 0.75
1/5 = 0.2

for example, take a look at this very famous question.
0.1 x 0.1
the most common mistake that students did was when they gave 0.1 as the answer. why this answer? because (most probably), they did the multiplication "directly", i.e. 0 x 0 = 1 and 1 x 1 = 1, so the answer is also 0.1.

better way?
0.1 x 0.1 can also be expressed as fraction as
1/10 x 1/10
now multiply numerators and denominators, we will get
1/100
which if we convert into decimals, we will get
0.01.

the same goes with the question 0.2 x 0.3, in which the answer is 0.06, not 0.6.

converting these numbers from one form to another is very useful, especially when we are dealing with multiplication (as shown above) and division. another example?

0.8 divide by 0.2.

some teacher taught the moving the decimal trick, but i really don't emphasize that trick to my students. we will discuss that later. now, lets convert these decimals into fraction, then we get

8/10 divide 2/10, and we can change divide to multiplication, and at the same time taking the reciprocal of the fraction on the right, to get

8/10 x 10/2

now, we cancel the 10s, and divide 8 with 2 to get 4 as our answer.

sounds tedious huh? well, first impression is not always true. again, i emphasize, this technique works very well for majority of the questions, NOT all questions. say we cannot do
1/3 + 1/2
by converting them into decimals, since 1/3 is a recurring decimal of 0.3333333...
I always emphasize this; use our own logics.

by the way, before i end this topic, i remember giving out these questions to my tutorial students:
(i) 0.2 x 0.8
(ii) 1.2 x 0.4
this "average" student tried to point out that my technique is useless, since he can calculate the first question directly, i.e. 0x0 =0 and 2x8 = 16, so the answer is 0.16. i just smiled to him, and asked him to do the second question on the whiteboard, and show his technique to the rest of his friends. proudly, he said this.
" this is easy...1x0 = 0 and 2x4 = 8, so the answer is 0.8. "

for readers, what is wrong here?
what should be the answer?

believe me, since that night, this student never argued with my technique, anymore... :-)

basics first

2008-04-28T07:29:00.000-07:00

okay. let's first review what we were being taught in school in doing the famous four operations; + - x /. during those time, i thought that BODMAS is the proper way of doing the four operations. the fact is...it is misleading IF we are not familiar with number concepts. we were taught - do the brackets first, then division, then multiply, then addition and lastly we must do the subtraction. this is very incorrect.

the proper way of viewing order of these operations is, yes we must do the brackets first, then either division OR multiplication, and either subtraction OR addition comes last, doing the ones that comes first from the left of the expression.

1. BRACKETS
2. DIVISION OR MULTIPLICATION
3. ADDITION OR SUBTRACTION

take a look at this example. 10 - 3 + 5. looks simple? personally, i don't think so. one time (last year if i'm not mistaken) i gave this question to my form 1 (year 7) students, and out of 24 students, only 2 got it right. what was their response?

10 - 3 + 5
= 10 - 8
= 2

can you spot what is wrong?

some people thought this is funny, but believe it or not, i did try giving this same question to my form 3 students (year 9) and form 5 students (year 11) from my tutorial school, and yes some of them still got this wrong. the response? as shown above.

so, how did they end up having this as their answer? BODMAS!!! According to this system, we must do addition first, so they added 3 to 5 to get 8, then they do the subtraction to obtain 2 as their answer. I am not saying they are wrong, this is what they called misconception.

if you are very familiar with directed numbers, even if you follow the BODMAS system, you will get the correct answer. why?

10 - 3 + 5

[by directed numbers, we MUST take note of the sign in front of the number. in this case, 3 is not a positive number. instead, it is a NEGATIVE number. so we have - 3 + 5 to obtain 2.]

= 10 + 2
= 12 ans.

we will obtain the same answer if we follow the order of operations properly, i.e. addition OR subtraction, which comes first from the left should be done first. in this case, subtraction comes first, so we do them first.

10 - 3 + 5
= 7 + 5
= 12 ans.

And this morning, i purposely gave the question below to my form 4 students. believe me, out of a total of about 60 students from 3 different classes, only about 20 of them got it right. the question?

7 - 2 x 3 - 2

what is your answer? drop them in the message board and see if you got it right. of course, no calculator. hehe...cheers

My introduction

2008-04-27T23:38:00.001-07:00

Assalamualaikum and hello to reader(s).

first of all, this tutorial blog is part of my initiative to broaden my teaching, thus reaching as many students out there as possible. Bear in mind though, that my tutorial focuses mainly on Mathematics, since i am a Math educator myself.

What I am trying to do is, Insya-Allah, post as many math questions as possible and at the same time, discuss the solution of that answer. I will try as much as possible to make the workings simple and easy to digest. At the same time, you can leave some message to me, ask me how to work out the answer and have some discussion.

One last thing though. The math that i will discuss here in this blog mainly for Year 11 below. Year 12 and above? hmmm...maybe some other time, although I do know how to do that. Again, this is part of trial, so I am trying to focus on Year 11 and below for the meantime.