2013 PSLE Discussions and Strategy

[Jennifer]

ngl2010:

slmkhoo:

[quote=\"Jennifer\"]However, if you r willing to forgo scoring any working marks for that qn, then ignore this suggestion

I believe that MOE has said that any mathematically valid methods (may not be the exact words because I can't remember) are OK for the PSLE? It's been 2 yrs since my daughter took PSLE, but I recall someone asked MOE and the answer was something like that.

Algebra is acceptable but no working mark will be given if the answer is wrong. So, if use algebra die die must get the answer correct [/quote] :yikes:

[Jennifer]

yogaqueen:

Hi there, I have some experience to share with regard to the use of Algebra in PSLE Math.


Firstly, at the beginning of this school year, I spoke to the school teacher. He stated that Algebra is acceptable but that method marks will not be awarded. So, the trick is, get the final answer right and you can the full marks. Or none.

In the middle of the year, feeling that this was not justified, I wrote to MOE on this particular question of using algebra. MOE did not categorically said Algebra is accepted (despite my re-questioning) but emphasized that any method will be awarded method marks as long as they are used correctly.

Strangely enough, weeks after my letter to MOE, my son came home to tell me his teacher (the same one I asked about Algebra) told everyone in class that Algebra is now acceptable as a method in PSLE Math and method marks will be awarded as long as they are sound.

So, I guess, bottomline is: don't worry that you will get zero marks if you don't get the final answer correct when using Algebra. You will get some marks for method.e.g stating the correct equations etc.

:rahrah:

:thankyou: for sharing.

[Jennifer]

ngl2010:

Jen, was the question 3 variables question?

For illustration purpose, I post the qn here. Would you classify this qn as having > 2 variables?

There are some red and blue marbles.
The marbles were packed into 2 containers.
At first, Container A contained 500 marbles and 2/5 of them were blue marbles. Container B contained 300 marbles and 1/5 of them were blue.

Find the total number of red and blue marbles that must be moved from Container A to Container B such that 3/5 of the marbles in Container A are red and 1/4 of the marbles in Container B are blue.

[zeemimi]

Jennifer:

ngl2010:

Jen, was the question 3 variables question?

For illustration purpose, I post the qn here. Would you classify this qn as having > 2 variables?

There are some red and blue marbles.
The marbles were packed into 2 containers.
At first, Container A contained 500 marbles and 2/5 of them were blue marbles. Container B contained 300 marbles and 1/5 of them were blue.

Find the total number of red and blue marbles that must be moved from Container A to Container B such that 3/5 of the marbles in Container A are red and 1/4 of the marbles in Container B are blue.

Is the answer 40 Blue and 60 red? Rather tedious. No need algebra. Use ratio. Using 2 variables will complicate everything. Best to express each Blue and red in each container as a fraction of the total number of marbles.

[Jennifer]

zeemimi:

Jennifer:

[quote=\"ngl2010\"]Jen, was the question 3 variables question?

For illustration purpose, I post the qn here. Would you classify this qn as having > 2 variables?

There are some red and blue marbles.
The marbles were packed into 2 containers.
At first, Container A contained 500 marbles and 2/5 of them were blue marbles. Container B contained 300 marbles and 1/5 of them were blue.

Find the total number of red and blue marbles that must be moved from Container A to Container B such that 3/5 of the marbles in Container A are red and 1/4 of the marbles in Container B are blue.

Is the answer 40 Blue and 60 red? Rather tedious. No need algebra. Use ratio. Using 2 variables will complicate everything. Best to express each Blue and red in each container as a fraction of the total number of marbles.[/quote]Yes, your answer is correct :rahrah:

This morning elder boy used ratio to solve but I hv prob understanding his method. Can u pm me how u solve or show the working here? Many thanks in advance.

Almost forgot to ask: would this type of qn appear in PSLE Maths paper?

[snowyqueen]

yogaqueen:

Hi there, I have some experience to share with regard to the use of Algebra in PSLE Math.


Firstly, at the beginning of this school year, I spoke to the school teacher. He stated that Algebra is acceptable but that method marks will not be awarded. So, the trick is, get the final answer right and you can the full marks. Or none.

In the middle of the year, feeling that this was not justified, I wrote to MOE on this particular question of using algebra. MOE did not categorically said Algebra is accepted (despite my re-questioning) but emphasized that any method will be awarded method marks as long as they are used correctly.

Strangely enough, weeks after my letter to MOE, my son came home to tell me his teacher (the same one I asked about Algebra) told everyone in class that Algebra is now acceptable as a method in PSLE Math and method marks will be awarded as long as they are sound.

I taught DD to use algebra to solve problem sums because I think it is more efficient than model method and faster. I had this concern and I checked with her H.O.D. Her reply was algebra is acceptable to be used in PSLE. I also asked about guess n check. It is acceptable if you can use it correctly even though there is straight solution. I taught DD in the worst scenario she really cannot figure out the right method to solve, use guess n check appropriately, not necessary applicable for all, only specific type of questions.

[ngl2010]

yogaqueen:

Hi there, I have some experience to share with regard to the use of Algebra in PSLE Math.


Firstly, at the beginning of this school year, I spoke to the school teacher. He stated that Algebra is acceptable but that method marks will not be awarded. So, the trick is, get the final answer right and you can the full marks. Or none.

In the middle of the year, feeling that this was not justified, I wrote to MOE on this particular question of using algebra. MOE did not categorically said Algebra is accepted (despite my re-questioning) but emphasized that any method will be awarded method marks as long as they are used correctly.

Strangely enough, weeks after my letter to MOE, my son came home to tell me his teacher (the same one I asked about Algebra) told everyone in class that Algebra is now acceptable as a method in PSLE Math and method marks will be awarded as long as they are sound.

So, I guess, bottomline is: don't worry that you will get zero marks if you don't get the final answer correct when using Algebra. You will get some marks for method.e.g stating the correct equations etc.

Thank you, yogaqueen.
:thankyou:

[ngl2010]

For Math’s Pattern problem, is it ok to count manually instead of using formula? This is assuming that the numbers are still reasonable.

[JohnYeo]

ngl2010:

For Math's Pattern problem, is it ok to count manually instead of using formula? This is assuming that the numbers are still reasonable.

what do u mean by reasonable?
Normally the first part still is n the second part is not.

[zeemimi]

Jennifer:

zeemimi:

[quote=\"Jennifer\"]
For illustration purpose, I post the qn here. Would you classify this qn as having > 2 variables?

There are some red and blue marbles.
The marbles were packed into 2 containers.
At first, Container A contained 500 marbles and 2/5 of them were blue marbles. Container B contained 300 marbles and 1/5 of them were blue.

Find the total number of red and blue marbles that must be moved from Container A to Container B such that 3/5 of the marbles in Container A are red and 1/4 of the marbles in Container B are blue.

Is the answer 40 Blue and 60 red? Rather tedious. No need algebra. Use ratio. Using 2 variables will complicate everything. Best to express each Blue and red in each container as a fraction of the total number of marbles.

Yes, your answer is correct :rahrah:

This morning elder boy used ratio to solve but I hv prob understanding his method. Can u pm me how u solve or show the working here? Many thanks in advance.

Almost forgot to ask: would this type of qn appear in PSLE Maths paper? [/quote]A: Blue-200 (200/800 = 10/40)
Red-300 (300/800 = 15/40)
B: Blue-60 (60/800 = 3/40)
Red-240 (240/800 = 12/40)
10+15+3+12= 40 parts
In order to keep the ratio of AB (2): AR (3) , one possible way is to move 2 parts of blue and 3 parts of red. This will result in 5 parts of BB And 15 parts of BR. Hence BB (1) : BR (3)
800 ÷ 40 × 2 = 40
800 ÷ 40 × 3 = 60