Thursday, October 19, 2017

My Maths Classroom.... Closure

Direct LINK to the form.

[Updated: 21 October 2017]
Click HERE to learn what your classmates shared about their learning experiences in the class :)

Responses to selected responses will be shared in the Google Classroom.
You will be alerted via an email when it is 'delivered'.

Saturday, October 7, 2017

Revision: SST 2016 Maths S1 Paper 2 Q4b

There are 2 ways to find xy :

Method 1: (as shown in the suggested solution document, in GoogleSite)
It uses the special products (or algebraic identities) to solve.
Note that we did not need to find x or y value in this method.

Method 2:

In this method, we attempt to solve 2 simple simultaneous equations to find out the values of x and y.
With this, we find xy.

Some of you actually use "Guess and Check" method, where you try to list down possible pairs of integers that can be add together to give 7, followed by check using the other equation. 
Do NOT use this method as it opens up many possibilities which would not worth the time to check one by one.

Revision: SST 2016 Maths S1 Paper 2 Q6

One strategy to solve this problem is to write down and organise the information available.
From there, try to pull the information together to form an equation to solve for the unknowns.

Revision: SST 2016 Maths S1 Paper 2 Q7

Given the speed of the following:
  • Adam     160 m/min
  • Bernard     120 m/min

Strategy: Put all information in a diagram and draw 'relationships' (with reference to the speed-time-distance formula) to form equations

Since we do not know the distance for the race, let it be d metres.
Since we are not given the time taken by Adam to complete the race, let the time taken be t minutes.
The 2nd diagram shows the position of Adam, Bernard and Charlie at t minutes.
Hence, what's common for all three boys is the duration, t minutes.

Using the formula, Distance = Speed x Time

With this, we know that distance covered by Charlie (at t min) = 800 m - 250 m = 550

Substitute d = 550 into first equation (i.e. time taken by Adam), we have
Time taken, t = 800 ÷ 150 = 5 minutes

Hence, Charlie's speed
= Distance covered/ Time taken
= 550 m ÷ 5 min 
= 110 m/min     (Ans)

Note: There are other 'shortcuts' to solve the problem. However, the above will give you an idea how to solve the unknown(s) systematically using the known relationships for speed-time-distance.

Revision: SST 2016 Maths S1 Paper 2 Q8

Watch the video clip (no sound) to understand the diagram

(i) Since the length of the paper is 30 cm, from the diagram, we note that
Height of letter in terms of x = 30 - x - x     cm, which is same as 30 - 2x    cm

(ii) Given the ratio Height : Width = 8 : 5
Since we can express the height of the letter in terms of x, we shall try to express the width of the letter in terms of x, too.

Refer to the line (in orange), width = 3 + x     cm

Now, with these information, we use the ratio to form the equation and use it to find x:

(iii) To find the perimeter of the letter, we need to find the (marked out in the diagram)

Monday, October 2, 2017

20171002: Revision - Algebra

Mentioned in class, there's more than one way to do (i).
I've presented 3 ways below how to show LHS of equation = RHS of equation.
We also spoke about NOT using any numbers to do the "shown" question. Remember that "hence" means make use of what is given in (i) to do (ii)

Practice for similar type of Question: CGS 2015 S2 Mid-Year Section A Q7

Saturday, September 30, 2017

6 AM Quiz: It's Algebra!

Click HERE to access the Quiz to submit your answers.
  • Click HERE to view responses

Answer scoreBonus score

For quick reference, the questions in the quiz are:

Suggested Solution
(updated: 3 October 2017)

It's Mensuration! It's Geometry! It's Amazing!

Friday, September 29, 2017

T4W3 Revision: Algebra

We discussed the following question during lesson.
It could be solved by applying our existing knowledge and skills:
- mensuration (area of square and area of circle)
- algebra - being able to square algebraic term, form an equation, and "removing" denominator in an equation

Before the lesson ended, you copied the following question to try over the weekend.
We shall discuss this question on Monday.

Thursday, September 28, 2017

29/8/17 G1 Math postings

HIHS S2 P2 Question 9


Homework for 29/8/17 Group 2

 This is the HIHS paper 2 question 9 solutions

This is the Crescent girls secondary 2 section A question 10

Group 3 NYGH paper 2 question 10 Latest one

Sunday, September 24, 2017

Group 1 Question 7

Image from Xing Zi
Posted on Behalf of Xing Zi because of technical problems.

Saturday, September 23, 2017

Saturday, September 16, 2017

6 AM Quiz: So Near yet So Far

Click HERE to access the direct link

Click HERE to view responses

Updated 22 Sep 2017

Tuesday, September 12, 2017

Pythagoras Theorem

Here are an interesting "proof" of Pythagoras' Theorem (using a simple set of Pythagorean triplets:


Click HERE to find out more about Pythagoras Theorem.

Below is a "proof" of the Theorem with water!

Mensuration: Volume of Cone and Pyramid

The volume of a cone fills up one-third of the volume of cylinder, i.e. we need three cones to fill up a cylinder.



Thursday, September 7, 2017

The "magic" can be explained with....

Source: Facebook page: 5 Unknown Facts

There seems to be some 'magical' links between the digits... however, if you apply algebra (i.e. factorisation), you would be able to figure out why or how the magic works :)

Saturday, August 26, 2017

6 AM Quiz: It's an equation? It's a line? It's Algebra!

Direct LINK

Click HERE to view responses
Group score:

  • Group 1: 1 points
  • Group 2: -
  • Group 3: 7 points
  • Group 4: -

Updated on 27 August 2017 (Sunday), 0830h

Friday, August 25, 2017

[Homework] 25 Aug: Basic Geometry & Mensuration (preparation)

Dear S1-07

(1) Basic Geometry
This morning, we conclusion "Basic Geometry" with discussions on Assignment 1 & Assignment 2, wit the online quizzes.

Assignment 1: Please review the angle properties you have in the handout.
Assignment 2: Complete the worksheet

Hand-in Assignments 1 & 2 on MONDAY (28 August 2017)

On Monday, you will be given a short quiz on Angle Properties (5 min)

(2) Mensuration
You were given the set of hand-outs for the Mensuration (Area and Perimeter of Planes).
Go through the handouts before the lesson.
You may watch the video clips in the post to help you understand how the formulae (area of parallelogram and trapezium) are derived, based on what you already know.

Attempt the riddle in the post, [Homework] Polygons: Who am I?
and the warm-up exercise, What's the Relationship?

Preparation for next week's lesson



You may take your time to read/ watch how the problems are solved. Complete this before Term 4 starts.

Watch the following examples. Each comes with a question and the explanation on how to solve the problem.
1. Pause the question. Read the diagram carefully and think what formula would help you to solve for the unknown.
2. Think how you would solve the problem - you may need to write down an equation in order to solve for the unknown.
3. Next, continue to watch the clip and listen to the explanation. Is this similar to what you have thought of? Look out for the presentation of the working.


[Discussion] Which Property Applies?

Let's refer to Assignments 1 & 2, and study the working provided.
Are you able to identify the relevant angle properties to explain the working?
Follow-up from Discussion:
Complete Assignments 1 & 2: To be submitted on 25 August 2017 (Friday)

[Homework] Polygons: Who am I?

Complete this piece of work before Monday's lesson.
We shall discuss the answers.

Click HERE for direct link

Click HERE to view responses

2017 (S1-07) Warming-up - What's the Relationship?

Click HERE for direct link

Click HERE to view responses

Thursday, August 24, 2017

Basic Geometry: How to present our working clearly?

Suggested Presentation: 
  • Step-by-step working
  • At any one time, only one angle property to be cited
  • Lines may be extended or additional lines may be added, if necessary
  • Other angles (that are not labelled) can be labelled you need to make reference to them along the way (as part of the working).

You may label the angles and indicate the angle properties in the diagram. However, this must be clearly written.

However, you must not combine steps when presenting your working!
(although some of you process the steps very quickly)

When presenting your working in writing:
You must not cite more than one angle property for a single step.
You need to break down the steps, write the working clearly with any relevant angle property, if applicable.

Monday, August 21, 2017

Recap: Names of different types of Angles

Basic Geometry: Talking about Dimensions!

Click HERE to view

[Homework] 21 Aug: Basic Geometry

Part (I) Attempt the following in the Google Classroom by Monday (21 August 2017)

Part (II) Attempt the following via the GoogleForm by Wednesday (23 August 2017)

Click HERE to access (2017 S1-07) Warming Up Question: Geometry (1)
<click HERE to view responses>

Click HERE to access (2017 S1-07) Warming Up Question: Geometry (2)
<click HERE to view responses>

Optional: Challenging Questions

You may email a clear photo of your complete solution of the challenging question to me ( by end of today (21 August 2017).

Remember to include clearly the Group Number.
Your responses will contribute to your group points.

Saturday, August 19, 2017

6 AM Quiz: Squeeze squeeze... what's your size?

Click HERE to access the 6 AM Quiz
<click HERE to see the responses>
You may click at the hyperlinks to see how your classmates approach the question.

Thursday, July 27, 2017

Geometrical Construction: For Discussion - Parallel Lines

Let's hear what Paul and Pauline say... Do you agree with them?

Ponder over what they said. We'll discuss this in the next lesson.

Geometrical Construction (1) Spot the Errors


1. Watch the clips and spot as many errors as possible.
2. Describe the error in "Comments" (e.g. What is wrong with the way the person did the construction? What should he do instead.)

Complete the task by Saturday (29 July 2017), 10 pm so that we can review your work and discuss in the next lesson.

Watch the clip and try to spot as many errors as possible.

Watch the clip and try to spot as many errors as possible.

Geometrical Construction (2) Little Red Riding Hood needs help!

Task to be completed by next Saturday (29 July 2017, 10 pm).

Additional Information:
Shortest distance between Grandma's house (G) and her house (H) is 10 km.
Draw a straight line on a plain paper with the scale, 1 cm to represent 1 km.
From there, construct the suggested path.

Take a photo of the constructed diagram and post it in the padlet below:

Direct LINK to the padlet.

Made with Padlet

Geometrical Construction (3) Where Shall We Meet?

Task to be completed by next Saturday (29 July 2017, 10 pm).

The location of the houses of three friends, Antonio, Benedict and Celine happened to form an equilateral triangle. They meet quite often to catch up with each other; however, none of them want to invite their friends home. To be fair, they decided to meet at a place that is most 'central' to all.

Point to ponder...
  • What would you suggest? 
  • How would you do it if you have their houses marked on a map already?

Note: There is a typo-error in the above diagram, it should be "Benedict"

Your Task: 

Assume that each house is 8 km from the two other houses.
(i.e. the length of the equilateral triangle is 8 km).
Taking the scale, 1 cm to represent 1 km, construct the equilateral triangle on a sheet of paper.

On this diagram, construct the relevant "some lines" to help you find the centre meeting point.
Hint: Perpendicular Bisectors, Angle Bisectors

Take a photo of your diagram (make sure it is clearly labelled) and post it in the padlet.

Direct LINK to access the padlet.

Made with Padlet

Monday, June 5, 2017

June Holiday and Semester 2 preparation

The Math folder that was given to your just before the June holiday contains the following:
  1. Common Test paper (corrections should have been completed)
  2. Common Test paper review (this is an error analysis paper based on the mistakes made by the students - they have to identify the mistakes made by circling them in green ink and stating the source/cause of errors.
  3. 2 timed practice papers (they have re-attempted the paper for selected questions) (these papers have been graded)
  4. Personal Reflections (Post Common test 2017) (They should review what they have written and have been told to set a feasible strategy for semester 2)
  5. Bridge to Algebra (Practice puzzles for essential skills) (set of worksheets to test their fundamental concepts of Arithmetic and Algebra - to be written in their exercise book with full working shown.)
  6. S1 June Holiday Engagement - sample questions from OECD's PISA ASSESSMENTS (refer (B))
  7. Practice Questions based on GCE papers (suggest timed practice: 1mark = 1.5 minutes) (will be graded by teacher)
  8. Geometrical constructions (note) (refer to (C))
  9. Geometrical constructions (assignment 1) 
  10. Geometrical constructions (quiz)

June Holiday Engagement - Consolidation and Revision

Through the lessons and assessments, your child would have realised by now that, all the knowledge and skills learned are inter-connected and they lay the foundation to subsequent topics. It is, therefore, important for them the master new skills and strategies though sometimes they could apply skills and strategies they already know to (in primary school). They have to recognise the need to expand their repertoire of skills.

During the June holiday, we hope that students could take some time to unwind and rest. 
On the other hand, we would also like them to keep in touch with what they have learned so that it would be easier for them to pick up the momentum when the new term starts in 5 weeks' time.

Based on the analysis of their test performance as well as global trends, we have put together selected questions from the sample questions from the OECD's PISA assessment (which are related to the S1 topics) as the June Holiday Engagement Challenge. 
  • The questions will require students to apply reasoning skills and articulate their train of thought clearly in the written form, which are competencies that 21st-century learners need to develop. 
The set is included in the Holiday work folder. On the whole, the task should not take more than 4 hours. They are advised not do all questions in a single attempt. They may stagger the tasks over a few days and attempt the tasks in any order. 
  • Submission: Term 3 Week 1 (to be attempted on the PISA paper provided and may use own paper where necessary)
  • Softcopies of the handout is available via the GoogleSite (login required). 
Please advise your child to manage his/ her time well as it could be very stressful if he/ she is going to cramp all the work to be completed just before the school reopens.

Planning Ahead

In Term 3, the following topics will be covered:
  1. Geometrical Construction
  2. Functions and Linear Graphs
  3. Data Handling
To prepare ahead, students can refer to the textbook for the above topics to read ahead.
Reading resources from the Ace-Learning will be assigned (optional) - for those who would like to preview the topics before Term 3 starts.

For Geometrical Construction
  • The topic was introduced last week when the class was briefed on the expectations and preparation needed before school reopens.
  • Study notes for this topic were given last week. 
  • Softcopy of the notes and resource materials are available at the GoogleSite.
  • This is a partial-Self-Directed Learning (SDL) topic. Video clips to guide construction skills are available in the GoogleSite.
For Data Handling and Functions and Linear Graphs
  • Study notes for this topic will be given in Term 3.
  • Data Handling begins with solving simple problems with 4 statistical representations that they learned in Primary School.
  • Functions and Linear Graphs will require them to apply knowledge and skills learned in Algebra, and they are required to plot graph.
  • No task on this topic is assigned.

Thursday, April 20, 2017



This topic is on Rate, Ratio and Percentage.
Attempt the task on papers.
Remember to label the parts and show your working clearly.
you may refer to additional resources for support.

Allocation of Task

COL Revision: Rate & Speed (Q1) The Traveller's Route

Attempt the task on papers provided.
Remember to label the parts and show your working clearly. Presentation must be clear.
Post your group's answer in the Padlet below. Remember to indicate the group name and the members who work on the task.

Eunice is driving from Singapore to Malacca, Malaysia.

Eunice is driving from Singapore to Malacca, Malaysia. She leaves Singapore Woodlands checkpoint at 08 30 and travels the first 60 km of the journey at an average speed of 25 m/s and the next 120 km at an average speed of 80 km/h. She stops at Muar for a 30-minute break before continuing the last part of her journey at an average speed of 90 km/h in 35 minutes.

(a) Convert 25 m/s to km/h. [1]
(b) What time does she reach Muar? Give time in the 24h notation. [3]
(c) Find the average speed for its entire journey, giving your answer in km/h. [3]

Made with Padlet

COL Revision: Rate & Speed (Q2) The Singapore Flyer

Attempt the task on writing papers.
Remember to label the parts and show your working clearly. Presentation must be clear.
Post your group's answer in the Padlet below. Remember to indicate the group name and the members who work on the task.

At a height of 165m, Singapore Flyer is one of the world’s largest Giant Observation Wheel and also one of Asia’s biggest tourist attractions.

The diameter of the Singapore Flyer measures at 150 metres, and it travels at an average speed of 0.24 metres per seconds. 

(a) Express its average speed in km/h

(b) How long (in minutes) does it take for the flyer to complete one revolution?

(c) The company is promoting the "dining capsule" concept, inviting people to dine in the capsule. If the meal lasts for one hour, how many revolutions would the diner have gone through for his meal?

Additional information

Circumference of Circle = 2 π r   where r is the radius and use π = 3.142

Video clip: Youtube
Information: with Padlet

Made with Padlet

COL Revision: Ratio (Q3) Precious Gold

Refer to the Handout and attempt the task on writing papers.
Remember to label the parts and show your working clearly. Presentation must be clear.
Post your group's answer in the Padlet below. Remember to indicate the group name and the members who work on the task.

By mass, Yellow Gold 18K is made up of 75% of Gold (Au), 15% of Silver (Ag) and the remainder is made up of Copper (Cu), by mass.

(a) Find, by mass, Au : Ag : Cu, giving your answer in the simplest form. [1]

(b) A goldsmith is tasked to make a piece of jewellery with Yellow Gold 18K. With 2.25g of Silver, how much of gold and copper would be needed to form the alloy? [2]

(c) If this piece of jewellery is to be melted into liquid alloy
(i) Find is the volume of the alloy. [3]
(ii) Compare the volume with that of a 15g of pure 24 carat gold, which has a greater volume – Yellow Gold 18K or 24 carat gold? [2]

Given that the density of Gold is 19.3 g/cm3, Silver is 10.49 g/cm3 and Copper is 8.92 g/cm3.


Watch the following clip for background info that would help you understand the context of the question better:

Mass, volume and density are related by an equation: density = mass ÷ volume

Made with Padlet