Q&A - P3 Math

[atutor2001]

Keroppi30:

:... I’m not trying to challenge your answers but I’m trying to address the questions raised by my dd. ....

Hi Keroppi30

Don't be too concerned, questioning our proposed answers. In fact, your query sets me thinking. Which is why I modified the question - hoping to find a solution to a more tricky type of math condition where only the whole number solution is allowed but is not explained explicitly in Pr Math. Lets just continue to question when there is ambiguity. It makes math more interesting and \"alive\".

Regards

[fanren]

Hi

for P3, can we use equation? for example let something be u, let something be w

then come out with 2 equations and solve the two unknown alphabets…

thought now school wants students to use reasoning, trial and error or those draw model type,

please enlighten me! my son going P3 next year

[tianzhu]

Keroppi30:

I’m not trying to challenge your answers but I’m trying to address the questions raised by my dd.

Hi

No worries, I’ve stayed long enough in Maths and Science threads to realise that a solution is only useful if it serves its purpose. The person asking the question must be able to understand it for it to be meaningful.

A vibrant forum where members offer differing views can only benefit us in the long run. So, we welcome your feedback as it helps to improve ourselves.

Best wishes

[Daddy]

HI,


A question need help.
\" Harry and Frank have 480 cards altogether. After Harry gve 90 cards to Frank, Frank has twice as many cards as Harry. How many cards do the two boys have at first.\"

Thanks

[Muffins]

Daddy:

HI,


A question need help.
\"Harry and Frank have 480 cards altogether. After Harry gave 90 cards to Frank, Frank has twice as many cards as Harry. How many cards do the two boys have at first.\"

Thanks

Hi Daddy, the two boys ALWAYS have 480 cards altogether. THAT DOES NOT CHANGE. So, if Frank has twice as many cards as Harry in the end, there must be three units of cards (2 units of Frank + 1 unit of Harry). So, 3 units = 480. 1 unit = 480/3=160. If Frank had 2 units - 90 cards at first, he had (160 X 2) - 90 = 320 -90 = 230 cards at first. And if Frank had 230 cards at first, Harry had 480 - 230 = 250 cards at first.

Regards.

[tutor_your_child]

Daddy:

\" Harry and Frank have 480 cards altogether. After Harry gve 90 cards to Frank, Frank has twice as many cards as Harry. How many cards do the two boys have at first.\"

Hi this is a question using 2-step method and model drawing.
Draw the \"after\" position first and you will be able to see it clearly.

http://www.postimage.org/

So each unit represents 160 (=480/3)
Harry has 160 after giving 90 to Frank, so Harry has 250 (=160+90) at first
Frank has 230 (=480-250) or (160*2=320; 320-90)

[Daddy]

Thanks alots


I understood. :love:

[Muffins]

Daddy:

Thanks alots


I understood. :love:

No problem, Daddy!

[Daddy]

Hi,


Problem sum question need help.
\"David has 5/8 as many stickers as Vincent. They have a total of 494 stickers.
a) How many stickers must Vincent give to David so that both of them will have the same number of stickers?
b) How many stickers does Vincent have in the end?

How to draw the model?

Is the quest said, David has 5/8 stickers and Vincent has 8/8 stickers??

Thanks...

[CeciliaHua]

Daddy:

Hi,


Problem sum question need help.
\"David has 5/8 as many stickers as Vincent. They have a total of 494 stickers.
a) How many stickers must Vincent give to David so that both of them will have the same number of stickers?
b) How many stickers does Vincent have in the end?

How to draw the model?

Is the quest said, David has 5/8 stickers and Vincent has 8/8 stickers??

Thanks...

David has [][][][][]
Vincent has [][][][][][][][]
Total 13[]
494 stickers divide by 13 = 38 stickers

Vincent has 38 x 8 = 304
David has 38 x 5 = 190

a) 494 divide by 2 = 247
Therefore Vincent must give David 247-190=57 stickers

b) Vincent has 304-57=247 in the end.