Sunday 20 October 2013

28 Sept...last session

This is the last session of Elementary Mathematics module.  I have enjoyed 1st session to the last session of this module.  Dr.Yeap has introduced alot of Math activities which help us to understand current primary school's Math concepts.  I have indeed learned alot of Math methods which I have never been introduced to during my school days.

Do you know area of triangle? 

Area of traingle -> 1/2 x base x height

But Dr. Yeap has taught other method which enlightened us.....

 
We were taught to think of other methods and Dr. Yeap showed us to cut part of triangle to place it on top portion of triangle to form a rectangle.  We will then be able to find area by using length x breadth. 
 
We were then been asked to set Math questions during our quiz.  It was quite tough yet fun as we need to use proper English sentence structure to make sure the other party able to understand the sentences and solve the problem.
 
Overall, Math is a subject which you can't memorize all the methods but to understand the concept.  It depends alot on your thinking skills using the right concept.......
 

Friday 18 October 2013

27 sept...Tangrams and BODMAS

Today, my group mates and I visited Singapore Art Museum for our group assignment.  It was a fruitful trip as I saw quite a number of abstract Art pieces at the galleries.  Hmmmm....i was wondering, how did these artists come up with such ideas and transfer them into their artworks.

After returning to our class, Dr. Yeap told us to use tangrams to form squares.  So what is tangrams?
This is what I have searched.....

The tangram is among the most popular of all dissection puzzles that exist today. A tangram is an ancient, unique, Chinese puzzle that consists of seven (geometric) pieces: one square, five triangles and one parallelogram. When all pieces are put together, they form one big square, when they are sperated, they form what is called a tan. Of the five triangles there are two large, two small and one medium in size. "The large triangle is twice the area of the medium triangle. The medium triangle, the square, and the parallelogram are each twice the area of the small triangle. Each angle of the square measures 90 degrees. Each triangle contains a 90 degree and two 45 degree angles, which makes them isosceles right triangles. The parallelogram contains 45 degree and 135 degree angles" (Bohning, G., et al., 1997, p. 3).

The relationship among the pieces enables them to fit together to form many figures and arrangements. However, the tangram is more than a seven piece square. When it comes to tangrams, the challenge is to arrange the pieces to form additional shapes. The seven pieces can be arranged to make anything form a rabbit, to the alphabet, to a person. "The tangram is the opposite of a jigsaw puzzle. Instead of fitting the pieces together in only one way, the seven tangram pieces can be arranged to make a great number of different figures" (Bohning, G., et al., 1997, p. 4).


 My groupmates and I have formed different sizes of squares using tangrams:

After the tangram activities, we were introduced to "BODMAS"...Have you heard of it?

If you've not heard about it, please read the text below:

Order of Operations - BODMAS

Operations

"Operations" mean things like add, subtract, multiply, divide, squaring, etc. If it isn't a number it is probably an operation.
But, when you see something like...
7 + (6 × 52 + 3)
... what part should you calculate first?

Start at the left and go to the right?
Or go from right to left?
Calculate them in the wrong order, and you will get a wrong answer !
So, long ago people agreed to follow rules when doing calculations, and they are:

Order of Operations

Do things in Brackets First. Example:
yes 6 × (5 + 3)=6 × 8=
48
 
no 6 × (5 + 3) =30 + 3=
33
(wrong)
Exponents (Powers, Roots) before Multiply, Divide, Add or Subtract. Example:
yes 5 × 22=5 × 4=
20
 
no 5 × 22=102=
100
(wrong)
Multiply or Divide before you Add or Subtract. Example:
yes 2 + 5 × 3=2 + 15=
17
 
no 2 + 5 × 3 =7 × 3=
21
(wrong)
Otherwise just go left to right. Example:
yes 30 ÷ 5 × 3 =6 × 3=
18
 
no 30 ÷ 5 × 3 =30 ÷ 15=
2
(wrong)

How Do I Remember It All ... ? BODMAS !

 
B
Brackets first
O
Orders (ie Powers and Square Roots, etc.)
DM
Division and Multiplication (left-to-right)
AS
Addition and Subtraction (left-to-right)

Divide and Multiply rank equally (and go left to right).
Add and Subtract rank equally (and go left to right)
 After you have done "B" and "O", just go from left to right doing any "D" or "M" as you find them.
Then go from left to right doing any "A" or "S" as you find them.
Here are some BODMAS questions for you to answer, enjoy......

Question 1

 
What is the value of 3 + 6 ÷ 3 × 2 ?
A    7       B    6       C    4     D  1.5

Question 2

What is the value of 5 × 3 - 12 ÷ 4 + 8


A   3        B    4       C   14      D   20
 
Question 3
 
What is the value of 5 × 4 - 2 × 3 + 16 ÷ 4

A   10      B  11½    C   18      D   34
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Tuesday 15 October 2013

26 Sept...Fraction, Multiplication and Geometry

Teaching Mathematics is all about formulas, steps, four operations knowledge...but today, I enjoyed the topic on fraction.  Dr. Yeap played a short nursery music video "Three Little Pigs" which I enjoyed alot.  After enjoying the sond, Dr. Yeap gave us a fraction problem to solve:

3 little pigs share 4 pizzas equally....how much should each little pig get?


 

 

 
 

These are my methods of solving this question...do you have other methods?

Polygon

Do you know what is a polygon?


A polygon is a plane shape with straight sides.

Is it a Polygon?

Polygons are 2-dimensional shapes. They are made of straight lines, and the shape is "closed" (all the lines connect up).
Polygon
(straight sides)
Not a Polygon
(has a curve)
Not a Polygon
(open, not closed)
Polygon comes from Greek. Poly- means "many" and -gon means "angle".

I have learnt the way of finding area of a polygon using the formula....it is amazing indeed!