Saturday, April 24, 2010

Ratio Word Problems (Solutions for HW Book Pages 132)


































































If you are still unclear about these solutions or the ones on Page 133, you're always welcomed to look for me :)

Please complete your Ratio worksheet (till Page 131) and the corrections over this weekend and hand it in on Monday, together with your signed yellow files.

See you guys next week!

Tuesday, April 20, 2010

Funny "Maths" T-Shirts

Dear 5/3,

Just something for you to have a good laugh about :)















A circle does not have any points or corners.















Do you also have trouble with fractions?


















PLEASE do not give this kind of answers. You will kill me (or any other of your Maths teachers) immediately.


















Remember what we learnt in Area of Triangles? A 90-degree angle means it is a right-angle triangle, thus it's always right :)

Some practice questions for Ratio

As quite a number of you did not manage to copy down or write out the questions in class today, I will be posting only the questions now for you to practise. I will post the solutions tomorrow so that you can check against your own answers. If you do not have the time to try them out at home, at least do take a look at how I present my answers (take note of the format). It is the standard I expect from you guys.


Q1. The number of beads in bag A to the number of beads in bag B is 9 : 5. There are 423 beads in bag A. How many fewer beads are there in bag B than in bag A?


Q2. Amy, Brenda and Celine shared 216 coins in the ratio 4 : 3 : 5. How many coins did Amy receive?


Q3. Express the ratio of 25 min to 1 h 20 min in its simplest form.

I'm putting up 3 questions for now, since you have the Remediation worksheet as your home practice for today. Please complete Pages 1 to 6 of the Remediation worksheet. See you guys tomorrow in class, and enjoy solving! :)

Wednesday, April 14, 2010

Important Facts on Area of Triangle and Ratio

Area of Triangle

1. Factors involved - base and height; where height is a perpendicular line at right-angle with the base and joining the base and the vertex (pointed tip) opposite the base.

2. Counting square units method and Cut-and-paste method

3. Formula - ½ x base x height

4. How to find a shaded part in a figure? - first, you have to find the total area of the figure (either triangle, square or rectangle). Then find the unshaded part (which can be 1 part or several parts). The last step would be taking the total area minus the area of the unshaded part.

5. How to find an unshaded part in a figure? - first, you have to find the total area of the figure (either triangle, square or rectangle). Then find the shaded part (which can be 1 part or several parts). The last step would be taking the total area minus the area of the shaded part.


Ratio

My 6 important points for ratio are:
1. No units - remember, only numbers are represented.
2. Show all your working - by working, I meant for you to show what number you divided or multiplied to get your answer.
3. Labels - make sure you write these at the beginning of every word problem so it helps you to see clearer and better.
4. Proportion - whatever you multiply with or divide by on one side of the ratio, you have to do exactly the same for the other side of the ratio too (meaning they always increase or decrease by the same amount).
5. Underline or highlight keywords (so you'll know which item/quantity comes first, which one comes second and so on).
6. Reducing to simplest form - make sure you know your equivalent ratios well. Reduce all your answers to the simplest forms for every question unless it states otherwise.

Monday, April 12, 2010

James Blunt - "My Triangle" song



Telly Monster: James! James! As soon as I heard you needed me I dropped everything! Well, almost everything! (Telly throws away the baseball he is holding) So, whats the problem? I'm here for you buddy!
James: Telly, I've lost something very special to me, and I think you're the only one who'll understand.
Telly Monster: Oh no, what did you lose?
James: Well, I can't really talk about it, but I can sing about it....

(The music to "You're Beautiful" starts to play)

This shape was brilliant

This shape was brilliant.
This shape was pure.
I saw three angles.
Of that I'm sure.
And I saw three pointy corners.
And then I saw three straight sides.
The top was very narrow and,
the base was all so wide.

Telly Monster: Wait, that sounds like...

A Triangle, My Triangle.
Oh Triangle it's true.
I saw your shape in a crowded place,
Now I don't know what to do,
Cos you're gone and I'm so blue.

I searched low and high,
over earth and sky,
but I can't find you Triangle,
Tell me why?
And I miss your base,
And I miss your height.
And my dreams are triangular every night.

My Triangle, My Triangle.
Telly Monster: So beautiful it's true.
Telly Monster: It must be those angles, put a smile on your face,
Telly Monster: Not to mention the hypotenuse.
But I need to know the truth,
Telly Monster & James: Oh Triangle where are you?

**hypotenuse is the slanted side of a right-angle triangle.**

Source: http://www.youtube.com/watch?v=o2Z6tDSb6c8&feature=fvst

Funny Maths Videos

Who do you agree with? - Part 1



Source: http://www.youtube.com/watch?v=88E0TYijc5I

Who do you agree with? - Part 2



Source: http://www.youtube.com/watch?v=7VCYgCNOuEM

Friday, April 9, 2010

Interesting Resources for Ratio

Websites


1. http://math.rice.edu/~lanius/proportions/index.html (Tutorial/Activity on Ratio)
2. http://www.math.com/school/subject1/lessons/S1U2L1GL.html#sm3 (Short tutorial, followed by questions on Ratio)
3. http://www.lead.com.sg (Tutorial and Activity on Ratio and Equivalent Ratios)
*Please log in to your LEAD accounts.
4. http://www.purplemath.com/modules/ratio.htm (Tutorial on Ratio; with examples and some teaching)
*Please stop after the geese and ducks example because the later questions are in American context and units.

Games & Quizzes
1. http://www.arcademicskillbuilders.com/games/ratio-blaster/ratio-blaster.html (Game on Equivalent Ratios)
2. http://math.rice.edu/~lanius/proportions/quiz1.html (Short quiz on Equivalent Ratios)
3. http://www.softschools.com/math/ratios/ratio_game/ (Quiz on Ratio - what we did in class)
4. http://www.softschools.com/quizzes/math/ratio_word_problems/quiz1309.html (Quiz on Ratio)

Introduction

Dear 5/3,

The purpose of this blog is for me to share online resources I have found with you. They are useful because they provide additional practice regarding the topics we learnt in class. Some of the games/quizzes can be really interesting as well - now, who says Maths is always boring?!

I will also post some challenging questions occasionally so you can try them at home or over the weekends. Solutions for these questions will be posted a week later, so you can check against your own work :)

If you have any questions regarding the lesson or if you need me to explain something, please do not hesitate to ask me in class or after school. You also know where to reach me through email as well.

Have a fun Maths journey!