PSLE Maths question. How to solve?

[Wind30]

for question 4, answer is 11.06am or 21 mins later is it??

 

 

yes. it is 7km/20kmperhour = 21 mins. As to why 7km, just think a little harder lor.

Edited October 17, 2009 by Wind30

[Legendary]

I think this thread is ridiculous! We are talking about primary 6 here. Really wonder who on this forum would be able to solve all these problems when they were 12. MOE really ought to be shot.

[Leslielai]

for question 4, answer is 11.06am or 21 mins later is it??

 

Correct.

 

It's in fact a very simple question.

 

Since we know Mei travels at 20kph and that she would have done half the distance + 3.5 km when Lin does half the distance, it is obvious that if she doesn't stop until Lin has done the entire distance, Mei would have done the entire distance + (3.5km * 2 = 7km).

 

Hence, the time taken for Mei to travel the hypothesized 7km will be the extra time that Lin needs to cover the 2nd half of her journey.

 

Since T = D/S, 7/20 = 0.35 HR or 21 MINUTES.

 

Add that on to 10.45 am and there you go, 11.06am.

 

 

[Leslielai]

I think this thread is ridiculous! We are talking about primary 6 here. Really wonder who on this forum would be able to solve all these problems when they were 12. MOE really ought to be shot.

 

Eh bro, I can tell you there has been no change in the standard of Mathematics throughout the years. These were the kinda questions I was being thrown when I took my PSLE some 12 years ago.

 

Only difference between now and then is that our parents didn't complain like the whiners these days do. Its also partly attributable to the fact that the quality of teachers these days has dropped to a point where I think its pathetic.

[Sir8]

Let's see how complaining and whining you will be :)

 

 

Eh bro, I can tell you there has been no change in the standard of Mathematics throughout the years. These were the kinda questions I was being thrown when I took my PSLE some 12 years ago.

 

Only difference between now and then is that our parents didn't complain like the whiners these days do. Its also partly attributable to the fact that the quality of teachers these days has dropped to a point where I think its pathetic.

 

[Redboy]

Heh.

 

For those who struggle to answer your children's primary mathematics questions the primary school way, you may post them in here. I will try my best to answer them all.

 

I wonder, is any one giving tuition part-time to pri sch kids?

Are u one of them?

[MarkMJProduction]

Dear miss/mrs,

 

Although I am only in primary five, I think I can teach you as my mathematics teacher has just thought my class the simultaneous concept. But, do you have PowerPoint 2007 or 2003? I can present it to you.

 

Yours,

Mark MJ

 

P.S. Reply soon!

[MarkMJProduction]

Dear whoever who wants to know the method to the last PSLE Mathematics question,

 

This is a PowerPoint Presentation on PSLE's last Mathematics question (click here to download (I can't seem to put it in the attachment) ). If you don't have PowerPoint, click here to download PowerPoint Viewer 2007. Watch and learn!

 

Best regards.

Mark MJ (an ordinary P5 student who just learnt the simultaneous concept)

[Alfisti168]

the new teletubby generation kids are really visual in their explanations.

 

Lagged my comp until siao [sweatdrop]

 

Anyway thanks mark. But do try simpler ways of explaining in future. There's no harm in typing. Clarity can still be there if you present your workings properly.

Edited November 11, 2009 by Alfisti168

[Vicky4Sgp]

Being a mother of primary school going children, i am struggling with extremely difficult maths homework they are bringing back everyday.

I scored straight A for maths from primary to uni but i am not able to explain or teach them. They kept saying that my method is very confusing and their teachers wont accept the way i solve.

 

For the question you have posted, I saw this OCTO channel video. Norman Tien explained using model drawing and I heard he is quite well known in teaching maths to PSLE students.

 

video link:

OR you can view from their company's website www.pslemath.com

 

 

Hope this helps :)

 

Vicky

[Bigbird2285]

Well, basically my daughter is in P6 and they are learning algebra. Infact during P5 too.

[Joseph22]

Being a mother of primary school going children, i am struggling with extremely difficult maths homework they are bringing back everyday.

I scored straight A for maths from primary to uni but i am not able to explain or teach them. They kept saying that my method is very confusing and their teachers wont accept the way i solve.

 

For the question you have posted, I saw this OCTO channel video. Norman Tien explained using model drawing and I heard he is quite well known in teaching maths to PSLE students.

 

video link:

OR you can view from their company's website www.pslemath.com

 

 

Hope this helps :)

 

Vicky

 

The problem i think is not with the question being difficult. Its just that you have learn too many formula liao so some of the most simple way of solving the question U learn in Primary school all forgotten liao.

its like that.

I ever saw this match question where you are given a right angle triangle to find the area. L and B. the only figure they gave you is the one on he longest side of the triangle.

the whole group of 10 poly student scratch our head trying to find a method that primary school student can used. End up, the answer is very easy to find.

[1fast1]

I ever saw this match question where you are given a right angle triangle to find the area. L and B. the only figure they gave you is the one on he longest side of the triangle.

the whole group of 10 poly student scratch our head trying to find a method that primary school student can used. End up, the answer is very easy to find.

 

A right triangle with a given hypotenuse (longest side) of x can have any area ranging from 0 to a maximum of (1/4)*(x^2) . See diagram. Red and green triangles have same hypotenuse, clearly different areas. So I don't know what your question asked, but what you wrote isn't right.

Edited June 30, 2010 by Turboflat4

[Joseph22]

A right triangle with a given hypotenuse (longest side) of x can have any area ranging from 0 to a maximum of (1/4)*(x^2) . See diagram. Red and green triangles have same hypotenuse, clearly different areas. So I don't know what your question asked, but what you wrote isn't right.

 

 

okay i think its also a equaliteral triangle... or is it isomatric?? both side same. longest side different.

[1fast1]

okay i think its also a equaliteral triangle... or is it isomatric?? both side same. longest side different.

 

Right triangles can't be equilateral, since equilateral triangles have all angles equal to 60 degrees (in right triangles, exactly one angle is 90 degrees). Right triangles can be isoceles (two sides have same length - in this case, the two sides at right angles have the same length).

 

If it's an isoceles right triangle, it has the maximum area of (1/4)*(x^2). Seeing it is easy. Proving it requires basic calculus.

Edited June 30, 2010 by Turboflat4

[Joseph22]

Right triangles can't be equilateral, since equilateral triangles have all angles equal to 60 degrees (in right triangles, exactly one angle is 90 degrees). Right triangles can be isoceles (two sides have same length - in this case, the two sides at right angles have the same length).

 

If it's an isoceles right triangle, it has the maximum area of (1/4)*(x^2). Seeing it is easy. Proving it requires basic calculus.

 

 

yes. by looking at it. we are all thinking of using calculator but realise primary school no calculator. then we use difficult formulae but also realise very funny.

 

Then the one who set the question say. Actually we think too much... just do a N X N / 4 you get the answer liao.

[1fast1]

yes. by looking at it. we are all thinking of using calculator but realise primary school no calculator. then we use difficult formulae but also realise very funny.

 

Then the one who set the question say. Actually we think too much... just do a N X N / 4 you get the answer liao.

 

I meant that proving that an isoceles right triangle has maximal area for a given hypotenuse requires calculus.

 

Finding the area (like in your question) is a trivial application of Pythagoras' theorem.

[Sabretan]

hai....all the fancy pedagogy when our kids haven't even master the fundamentals...

 

 

I am old house....means I believe in memory work to build up the fundamentals b4 going to HOTS such as applications...

 

it is like building a house...if the fundamentals are no good, no matter how creative or how well u package the exterior, a real storm will show u its worth....