Q&A - P4 Math

[Charnic]

Sorry, is packet to the bag. Pls assist to draw the model. TIA.

[tianzhu]

CNS:

Sorry, is packet to the bag. Pls assist to draw the model. TIA.

Hi

A student should take note that that the total amount of flour remains the same before and after.

Bag ----- 2 units
Packet ----- 1 unit

3 units ------ 9183

1 unit ------ 3061 (This is the amount of flour left in the packet).

Best wishes

[Charnic]

But if we want to use cut and transfer method, possible ? When I told my gal about the way you mentioned, she asked me to draw the model on pre and post, that is where i am stuck ? I am also quite confused when to use what method ? Sigh.. :oops:

[tianzhu]

CNS:

But if we want to use cut and transfer method, possible ? When I told my gal about the way you mentioned, she asked me to draw the model on pre and post, that is where i am stuck ? I am also quite confused when to use what method ? Sigh.. :oops:

Hi

MD is one of the many problem solving heuristics in primary school maths. It’s not the only one.

From the way your question is worded, there is no necessity to go further than throwing 2 boxes for bag and 1 box for packet.

The question asks for the amount of flour left in the packet which is represented by 1 box.

If the question asks “How much flour was transferred from the packet to the bag? Then, it’s is (4157-3061) which is 1096.

A student may want to add some arrows to show the transactions during the transfer, it’s possible, but the issue is “Is it necessary?”

Best wishes

[MathIzzzFun]

CNS:

But if we want to use cut and transfer method, possible ? When I told my gal about the way you mentioned, she asked me to draw the model on pre and post, that is where i am stuck ? I am also quite confused when to use what method ? Sigh.. :oops:

Hi

here's the model...

http://i44.tinypic.com/1z5kndj.jpg\">

as mentioned by tianzhu, MD is not the only approach to problem solving and in this case, using the MD to show the transfer is a little cumbersome. The better way is to see that the total amount of flour remained the same and after the transfer, there were 3 units of flour in total -> which is the solution provided by tianzhu.

cheers.

[corneyAmber]

firefly38:

ksi:

[quote=\"Champion\"]:?: need help with this question as well :thankyou:


There were twice as many boys as girls at the school hall.
After 15 girls had left, the number of boys was thrice the number of the remaining girls. How many students wee there at the school hall?

http://i41.tinypic.com/2d1sg8z.jpg\">

Hi ksi,
From the model provided, it seems to me that total number of girls was 45 (u=30.. u+15.. 30+15), and total number of boys was 90 (45x2), hence total number of students at the hall should be 135 (45+90)?
But 120 seems right too (u=30.. 30x4), from the second model that you drew for the boys (the top most bar).
Appreciate your clarification.. Thanks![/quote]

I also pondered for a while. I believe Champion could solve this problem but got stumped by the English. The whole question was written in past tense. So when it asked 'how many students were there at the school hall?\" I took it as the students after 15 left off as it was asked immediately after stating 15 students left the hall. If the question was \"how many students were there at the school hall AT FIRST?\" Then I would put 135 as the answer. So to me, this question creates this kind of lousy ambiguity, it is a bad question.

[Champion]

ksi:

I also pondered for a while. I believe Champion could solve this problem but got stumped by the English. The whole question was written in past tense.

:oops: :oops: No lei, I stared at the question for 10 minutes and suddenly the :snooze: :snooze: instinct came in lioa

ksi:

So when it asked 'how many students were there at the school hall?\" I took it as the students after 15 left off as it was asked immediately after stating 15 students left the hall. If the question was \"how many students were there at the school hall AT FIRST?\" Then I would put 135 as the answer. So to me, this question creates this kind of lousy ambiguity, it is a bad question.

:thankyou: :thankyou: ksi once again for your input; appreciates much :celebrate:

[corneyAmber]

Champion:

ksi:

I also pondered for a while. I believe Champion could solve this problem but got stumped by the English. The whole question was written in past tense.

:oops: :oops: No lei, I stared at the question for 10 minutes and suddenly the :snooze: :snooze: instinct came in lioa

ksi:

So when it asked 'how many students were there at the school hall?\" I took it as the students after 15 left off as it was asked immediately after stating 15 students left the hall. If the question was \"how many students were there at the school hall AT FIRST?\" Then I would put 135 as the answer. So to me, this question creates this kind of lousy ambiguity, it is a bad question.

:thankyou: :thankyou: ksi once again for your input; appreciates much :celebrate:

Humble Mummy....next time I call you hummy mummy dearly.....

[Champion]

ksi:

Humble Mummy....next time I call you hummy mummy dearly.....

WCW:

hummy champ sotong mummy dearly

:oops: :oops: I am still the same sotong champion mummy

[corneyAmber]

Hummy Champo Mummy, is this question from school worksheet or assessment book?