Q&A - P3 Math

[24hr-mum]

got this question from andrew er’s maths companion p3 bk but no working shown in the bk. only ans.

how to do this without algebra?

if aziz buys 6 pens, he will have $6 left
if he buys 8 pens, he will be short of $2.
how much $ does he have?

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henry has some apples
when he puts them equally into boxes of 3, he will have 5 more boxes than if he puts them into boxes of 4. how many apples does he have?

[ksme]

24hr-mum:

got this question from andrew er's maths companion p3 bk but no working shown in the bk. only ans.

how to do this without algebra?

if aziz buys 6 pens, he will have $6 left
if he buys 8 pens, he will be short of $2.
how much $ does he have?

---------

henry has some apples
when he puts them equally into boxes of 3, he will have 5 more boxes than if he puts them into boxes of 4. how many apples does he have?

Here're my answers.

if aziz buys 6 pens, he will have $6 left.
if he buys 8 pens, he will be short of $2.
how much $ does he have?

Aziz has $6 after buying 6 pens. When he buys 8 pens, (ie additional 2 more pens), he needs to pay $6 (what he had) + $2 (the shortfall he needs).

Therefore, each pen costs $4 ($8/2pens).
6 pens cost $24 (6 x $4).
Total amount he has would be $30 ($24+ $6 he left).

To cross check if this answer is correct:
The cost of 8 pens would be $32 ($4 x
He has $30 so he is short of $2 if he wants to buy 8 pens.

----------------------------------------------------------------
henry has some apples
when he puts them equally into boxes of 3, he will have 5 more boxes than if he puts them into boxes of 4. how many apples does he have?

5 more boxes of 3 apples each would mean 15 apples.
15 apples if redistributed to the boxes of 3 apples each to make them boxes of 4 apples each will mean that there were 15 boxes.
Therefore, total number of apples = 15 x 4 apples each = 60 apples.

Hope the above helps.

[24hr-mum]

thanks ksme. ur answers to both qns are correct.


re 1st question, each pen is $4 because 8/2.
what is the 8? i know 2 is 2 additional pens.

also, how to present the answer? the child wont be able to explain the way u explain on paper.

and the main problem or challenge would be: how to teach the child to analyse the question so that she can get the method herslf and rem it all the time, instead of finish this questn, and next time similar questn appears she say i duno again or forgot the mthd…this is my greatest headache… no matter how many questions she is exposed to, she will nvr rem the mthd.

[Nebbermind]

AFAIK, the schools teach MODEL when the kids r in P2. If the kid still struggle with drawing models when in P3, then better pick up the P2 Math book again else it’ll be a struggle ahead!!


juz my 2c.

[24hr-mum]

can the two questions i post be solved by model?

[ksme]

24hr-mum:

can the two questions i post be solved by model?

Yes, Can be solved by model but I can't draw the model on computer. Perhaps Tianzhu can help. He is an angel on these threads helping many people.

I couldn't sleep last night so when I saw your questions, decided to get my brain to exercise. Helped me sleep after that.

[tianzhu]

Hi


Hope this helps.

This is a question on “Excess and shortage”.
Some may call it “Gap and Differences” concept.

Best wishes

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[ksme]

Thanks Tianzhu. What about the 2nd qn on apples?


As I said earlier, you are an angel for us parents. 

[tianzhu]

ksme:

Thanks Tianzhu.

Hi

You're welcome.

Best wishes

[tianzhu]

Hi


Hope this helps.

Best wishes.

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