Q&A - P3 Math

[dazzlego]

AgonyMum:

Thanks dazzlego for your help

Could you help to solve question 2 as well? I still could not solve it
BTW, can models be used to solve these 2 questions? Will it be an effective method?
Thanks in advance!

Hi AgonyMum,
Yes, you may draw the model. However, you still need to analyse the question in order to draw it.
Here is the model for question 1
http://i49.tinypic.com/30m8pcm.jpg\">

And for question 2, sokk has already helped you to draw the model and solve it

sokk:

Hi AgonyMum,
Hope this help, by using models for question 2.
Start by drawing the number of units for Pail Z . Since 1/6 (1 unit) of d water was poured out, that means 5/6 (5 units) of the water was left.
Since all 3 pails would hv d same volume of water left, u can proceed to draw 5 units each for Pail Y n Pail X.
Since we do not know d value of 1 unit, I wrote +500ml for Pail Y together with d 5 units already drawn.
Draw 5 more units for Pail X since d amt of water poured out from Pail X is 5 times that of Pail Z.

http://i46.tinypic.com/11igxf7.jpg\">

[dazzlego]

CayennePepper:

I try...

1567+865=2432 (total no. of chairs)
2432-769 red chairs=1663 blue chairs

That's my guess at how most kids will answer this.


BUT i find the phrasing open to interpretation.

-- After he had painted 1567 chairs, Mr Yeong still had another 865 chairs to paint. Given that he painted 769 chairs red, how may chairs were painted blue?

Seems like the 865 chairs is a red herring that should be ignored, since Mr Yeong had actually painted only 1567 chairs. So out of that, 1567-769=798 were painted blue.

What was the given answer?

What is your answer if u are the student, CayennePepper?
1663 or 798 :evil:

[AgonyMum]

Yeah, yeah! Thanks so much, sokk and dazzlego

I can understand both questions and their solutions now !
Really appreciate your help. THANKS!

[Riolu]

dazzlego:

CayennePepper:

I try...

1567+865=2432 (total no. of chairs)
2432-769 red chairs=1663 blue chairs

That's my guess at how most kids will answer this.


BUT i find the phrasing open to interpretation.

-- After he had painted 1567 chairs, Mr Yeong still had another 865 chairs to paint. Given that he painted 769 chairs red, how may chairs were painted blue?

Seems like the 865 chairs is a red herring that should be ignored, since Mr Yeong had actually painted only 1567 chairs. So out of that, 1567-769=798 were painted blue.

What was the given answer?

What is your answer if u are the student, CayennePepper?
1663 or 798 :evil:

Hmm... ... interesting

If this is a GEP type qn, answer can be 798 because \"Mr Yeong had actually painted only 1567 chairs\" and should ignore the \"865 chairs\" as yet to be painted. If this is a usual school exam question, answer may be 1663 as i believe is answer by most.

Well, open to interpretation lah! so what is the answer?

[CayennePepper]

dazzlego:

CayennePepper:

I try...

1567+865=2432 (total no. of chairs)
2432-769 red chairs=1663 blue chairs

That's my guess at how most kids will answer this.


BUT i find the phrasing open to interpretation.

-- After he had painted 1567 chairs, Mr Yeong still had another 865 chairs to paint. Given that he painted 769 chairs red, how may chairs were painted blue?

Seems like the 865 chairs is a red herring that should be ignored, since Mr Yeong had actually painted only 1567 chairs. So out of that, 1567-769=798 were painted blue.

What was the given answer?

What is your answer if u are the student, CayennePepper?
1663 or 798 :evil:

I pick... 798 lah
:nailbite:

[CayennePepper]

Riolu:

dazzlego:

[quote=\"CayennePepper\"]I try...

1567+865=2432 (total no. of chairs)
2432-769 red chairs=1663 blue chairs

That's my guess at how most kids will answer this.


BUT i find the phrasing open to interpretation.

-- After he had painted 1567 chairs, Mr Yeong still had another 865 chairs to paint. Given that he painted 769 chairs red, how may chairs were painted blue?

Seems like the 865 chairs is a red herring that should be ignored, since Mr Yeong had actually painted only 1567 chairs. So out of that, 1567-769=798 were painted blue.

What was the given answer?

What is your answer if u are the student, CayennePepper?
1663 or 798 :evil:

Hmm... ... interesting

If this is a GEP type qn, answer can be 798 because \"Mr Yeong had actually painted only 1567 chairs\" and should ignore the \"865 chairs\" as yet to be painted. If this is a usual school exam question, answer may be 1663 as i believe is answer by most.

Well, open to interpretation lah! so what is the answer?[/quote]i am dying to know!
i went around asking kids and interestingly the ones good in EL/math all said 798 should be the answer.

[Kiatkhim]

Thanks v much for all your replies. Given answer by school is 1663. 1663 is full 4 marks while 798 is only 1 mark (for consolation!). DS and friends in school usually good in Maths also puzzled.

[Riolu]

Kiatkhim:

Thanks v much for all your replies. Given answer by school is 1663. 1663 is full 4 marks while 798 is only 1 mark (for consolation!). DS and friends in school usually good in Maths also puzzled.

:scratchhead:

[CayennePepper]

hahahaha, there are no red herrings in p3 maths?

[dazzlego]

CayennePepper:

dazzlego:

[quote=\"CayennePepper\"]I try...

1567+865=2432 (total no. of chairs)
2432-769 red chairs=1663 blue chairs

That's my guess at how most kids will answer this.


BUT i find the phrasing open to interpretation.

-- After he had painted 1567 chairs, Mr Yeong still had another 865 chairs to paint. Given that he painted 769 chairs red, how may chairs were painted blue?

Seems like the 865 chairs is a red herring that should be ignored, since Mr Yeong had actually painted only 1567 chairs. So out of that, 1567-769=798 were painted blue.

What was the given answer?

What is your answer if u are the student, CayennePepper?
1663 or 798 :evil:

I pick... 798 lah
:nailbite:[/quote]If this is a competition question then u are correct!
However, this is a normal P3 Math question right? So the answer should be 1663.
Nowadays, this became quite a common case in P3 (even P4) maths questions already. I have no idea why didn't the questions setter put more effort in sentencing P3 Maths questions.
:siao: