Q&A - P3 Math

[tianzhu]

24hr-mum:

how to present the answer? is it draw models?
does the sch teach or we must somehow source the answers?

Hi

I’d say a MD helps students to arrive at the answers; it helps one to \"see\" Maths.

If you get more familiar with “Excess and shortage “types of questions, you may do away with drawing models.

I believe all questions in school exams should be covered in syllabus.

Best wishes

[rrjan]

Could anyone help me on this question please? How to show answer with model for this qsn?


Linda & Roy have a total of 255 stamps. Half or Linda’s stamps is twice as many as Roy’s stamps. How many stamps does Roy have?

Sincere Thanks,
Jan

[ksme]

rrjan:

Could anyone help me on this question please? How to show answer with model for this qsn?


Linda & Roy have a total of 255 stamps. Half or Linda's stamps is twice as many as Roy's stamps. How many stamps does Roy have?

Sincere Thanks,
Jan

I can't draw model. However, this is how I would work out the answer:

Half of Linda's stamps is twice as many as Roy's stamps
=> all of Linda's stamps would be 4 times as many as Roy's stamps

Total 5 parts (Linda's 4 parts + Roy's 1 part) => 255 stamps.
1 part = 51 stamps.

Therefore, Roy has 51 stamps.

[rrjan]

Thanks for your kind help KSMe, i think my boy will be able to understand your explaination as its very clear :celebrate:

[concernParent777]

Hi all,


I am stucked in a P4 Math question while helping out my son, any idea where I can post it? Thanks

[autumnbronze]

Hi,


:rahrah: :welcome: :welcome: :rahrah:

You may direct yourself to this link:

http://www.kiasuparents.com/kiasu/forum/viewtopic.php?t=149&start=650

[concernParent777]

Thanks, but I have taken a picture of the question, how do I upload the pic?

[tankee]

concernParent777:

Thanks, but I have taken a picture of the question, how do I upload the pic?

please see instructions here

http://www.kiasuparents.com/kiasu/forum/viewtopic.php?p=132258#132258

[Bunny27]

Hi Maths Guru,


Below are 2 questions which I needed help :

a) A,B and C shared some comics among them. A received 2/5 of them while B received 5/6 of what he and C received altogether. If A received 180 more comics than C, how many comics did B received?

b) A can of juice had a mass of 1100g when it was 1/4 full. Another identical can had a mass of 3200g when it was 5/6 full. What was the mass of each can when it was filled complete with juice?

[Pen88n]

Bunny27:

Hi Maths Guru,


Below are 2 questions which I needed help :

a) A,B and C shared some comics among them. A received 2/5 of them while B received 5/6 of what he and C received altogether. If A received 180 more comics than C, how many comics did B received?

b) A can of juice had a mass of 1100g when it was 1/4 full. Another identical can had a mass of 3200g when it was 5/6 full. What was the mass of each can when it was filled complete with juice?

a) Think of a model with 10 parts,
A = 2/5 = 4 parts
B = 5/6 of the remainder = 5 parts
c = 1/6 of the remainder - 1 part
So the model will looke like this: AAAABBBBBC

Diff between A and c = 3 parts = 180
1 part = 60
B has 5 parts = 60 x 5 = 300

b) Diff between 2 cans: 5/6 - 1/4 = 10/12 - 3/12 = 7/12
When can is filled with 7/12 juice, the juice (without the can) will weigh 3200g - 1100g = 2100g
1/12 can of juice (without can) will weigh 2100g/7 = 300g

3/12 can of juice with can weighs 1100g
Add another 9/12 juice to fill up the can, that will add in anther weight of 300g x 9 = 2700g
Total weight of can filled with juice = 2700g + 1100g = 3800g