PSLE Math Qns

[HdBanger]

my sis is doin pri sch tuition, and i had a discussion with her abt these qns yday.

 

algebra (basic forming and dealing with simple variables) are taught in p6, effective last year. but i don't think it's fully implemented to run in the exams. at least not for now.

 

so, if based on algebra, most (if not all) of us here can answer the qns. if you exclude usage of algebra, it becomes a challenge.

 

i did the qns using guess and check and model drawing, like what one bro here said. and the ans can be obtained. to me, q2 was designed to test the understandin of the qn, the workin is straightforward.

 

q3 is also not tough, just that most kids would probably go towards equal volume instead.

 

i had problems with q1 instead, and the only way to go for them, is guess and check. 228 is for 19units, while the ratio of 4:1 gives 5units. which means any final total needs to be in multiples of 5. whatever you subtract from the original, will be shared equally by both shops. i worked in 10units, which means you move down fr 220 to 140, and get the answer out.

 

it's a hoo haa this year, cos the kids come to my place to be coached by my sis, and most of them i can see, don't have the focus/mood to study. even my sis had a tougher time with them. that's how they couldn't cope with the standard.

 

it's just kinda sad that parents pointed the finger quickly to the sch/teacher/principal/moe, instead of lookin at what their kids failed to prepare themselves for.

 

for those who wondered how i know, i had the privilege (and support of my sis) to coach a p6 girl this year, for the first time. she feedback that it was tricky, but she had time to finish the paper, and check through in half hour. i hope she does well.

[Rayleigh]

Oh...I was tricked by the sentence " the rest are stacked up".....hehehe.....

[King]

KNN!!!

i read thorugh, i still do not understand...

i think i below average

[Butakim]

Don't we need to include the number of chairs stacked up? The question is asking the total number of chairs, not the total number of chairs that are arranged.

[King]

Let me look at question one.

In order to even begin to determine the amout of rice sold by each shop we need to take into account the geo location of Shop A and Shop B. The location would then allow us to determine the gravitational factor which arises from the

[King]

wolveman, u go and die lah ,KNN, read your post i got headache!!!

[Wolverman]

[Batliwala]

pretty simple questions. My daughter studying in Primary 5 in a Private Indian International School was able to solve these questions in 10 minutes getting correct published answers. Probably students in Schools here were not exposed to simple ratio questions.....

[Wolverman]

many stupid singaporean kids ah

[Panda]

There are no stupid kids. There are only stupid parents.

[Batliwala]

gosh I did not say that.....sorry to hurt sentiments if I was assumed to mean that.....

 

Cheers

[Redboy]

Don't we need to include the number of chairs stacked up? The question is asking the total number of chairs, not the total number of chairs that are arranged.

 

not need to include no of chairs stacked up.

After careful analysis, you can actually treat the terms 'rows of 13'& 'rows of 7' as if they are not there.

First, let x be total no of chairs, so we can deduce the following:

6x/14 = no of chairs in rows of 13

7x/14 = no of chairs in rows of 7

 

If you dun believe, let me prove it:

 

Now, form an eqn representing no of rows of 13 and no of rows of 7. We have:

6x/(14*13) = no of rows of 13

7x/(14*7) = no of rows of 7

 

Now, using the above eqn, I form another eqn representing the total no of chairs in rows of 13 & row of 7. We have:

 

6x/(14*13) multiplied by 13 = 6/14 x

7x/(14*7) multiplied by 7 = 7/14 x

Which is the original eqn in first step!!

 

Now, 7x/14 - 6x/14 = x/14

x/14 = 112

x = 14 * 112 = 1568

 

My method sounds a bit like reverse engineering hor!

But hey! It proves MOM are pretty cunning to set such qns!

In a nutshell, the 'rows of 7' and 'row of 13' are the killer words!

Edited October 22, 2007 by Redboy

[Butakim]

thanks...

 

was stuck trying to factor in the chairs that are stacked. then cannot solve liao.

[Porker]

I can't believe you guys spend so much time reading that few lines...

 

Like Nike said.. Just Do It

[Wolverman]

stupid ppl whahaha

[Porker]

[Wolverman]

[Ahhuat]

im puzzle too. I believe they are giving these kids lower secondary maths questions to solve but without the use of algerbra. Its to induce creative thinking wor.....thats what MOE claim.

 

If one's kid develop thier creatively later.......then hon-gan liao.

 

these qns are the harder ones.. every exam has harder ones.. to separate the really good from the good.. it's been there since our time..

 

the only reason why we cant do it is becos our brains rotten liao.. i cant even add numbers up to a hundred without a calculator anymore...

 

in fact, blame the education of our time.. not the one now.. kids are getting better education.. we should stop complaining but start worrying for when our kids start taking over our jobs and we are redundant