Q&A - P4 Math

[sleepyqueen]

smartmummy:

sleepyqueen:

[quote=\"smartmummy\"]Pls help! tomorrow maths exam...

2 files and 3 pens cost $12.50.A pen cost 75cents less than a file.How much does a pen cost?
Thank you in advance.
I did as follows
cost of pen []
cost of file []+75cents
5u+$1.5=$12.50 if U is to represent a pen then the 5U = $12.50 -$1.5 = $11, then 1U = $2.20 Why we need to add $1.5?,sorry can't get it.My son also said something like this. Should be subtract $1.50
You see
2 files = 2 pens + 1.50 ;
therefore 2 files + 3 pens = (2 files + 1.50) +3 pens = $12.50

5u=$11.50
u=$2.30
A pen costs $2.30.

Is it correct?
How to do by substitute method? My son told a method (his own invention),I can't agree with him.

3 pen cost $0.75 x 3 = $2.25 more than a file.
therefore 5U of files = $12.50 - $2.25 = $10.25
1U = $2.05
A file cost $2.05
And hence a pen cost $2.05 + $0.75 = 2.80

Check : total cost of 3 pens: 3 x $2.80 = $8.40
total cost of 2 files : 2 x $2.05 = $4.10
total cost of 2 files and 3 pens = $12.50 #

Thank you for the answer.[/quote]Alert smartmummy!!! I made a mistake in the question, the cost of the pen is supposed to be less than the file. Here is the corrected answer:

3 pen cost $0.75 x 3 = $2.25 less than a file.
therefore 5U of files = $12.50 + $2.25 = $14.75
1U = $2.95
A file cost $2.95
And hence a pen cost $2.95 - $0.75 = $2.20

Check : total cost of 3 pens: 3 x $2.20 = $6.60
total cost of 2 files : 2 x $2.95 = $5.90
total cost of 2 files and 3 pens = $12.50 #


Thanks verykiasumummy for pointing out. :salute:

[smartmummy]

ok sleepyqueen, got it.Thanks verykiasumummy!

[optimistforum]

smartmummy:

optimistforum:

Thank you ruohoo97


On a different note - to all posters.

My P4 DS (just started P4 here in the UK) is struggling on the P3 Challenging Maths (Sabdya Sundar EPH). Is this normal, I know it is a hard book, but should he not be on to the P4 book by now. Any advice appreciated.

Thanks

I thought ur boy can do one year advance with the help of tutoring. :?

I bought P4 book, I don't have P3 one.After reading ur post,I flipped through the book,I think now(as end of the year and do many problem sum qn in school) my son can do.but I never give any sum from this book.I kept this book aside as it consists of quite thinking qns.I tried some qn from Maths Olympaid by Terry Chew.My son didn't like to do.So I stopped.I only depend on Past year papers.My son doesn't have motivation or willingness to do challenging qns.He easily give up.

Hi smartmummy
DS does have tutoring but struggles with maths as he is prone to schoolboy errors. He also reads too quickly and misses the key information.
On a different not, I have the Terry Chew Maths Olypiad Books too. I flit between Challenging Maths P3 and Olympiad Beginner (9-10). Which book do you think is more stretching with higher order and novel problems?

[smartmummy]

Hi optimistforum,


I am an exam-oriented person. :oops: So I prefer Maths Olympiad as the qns coming for exams[usually one qn in section C].In MO they catergorised the qns, so it is easy to drill.In Sandhya Sundar,the qns mixed up,So we have to identify the qn first[more qns based on syllabus but more difficult than usual exam papers' qns,if the person willing to challenge then no harm to try otherwise is kill the person's interest in Maths].After doing MO then can try SS.JMHO.

[Jamesbond]

My DS has scored 100 in Maths and 96 in Science for his SA2....I am very glad to share his marks with u all....The whole credit goes to Kiasuparents for the timely help in clearing all his doubts then and there. :grphug: ....My heartfelt thanks to all the parents.... :salute:


:thankyou:
:udawoman: :udaman:

[pchong]

Jamesbond:

My DS has scored 100 in Maths and 96 in Science for his SA2....I am very glad to share his marks with u all....The whole credit goes to Kiasuparents for the timely help in clearing all his doubts then and there. :grphug: ....My heartfelt thanks to all the parents.... :salute:


:thankyou:
:udawoman: :udaman:

Wow! How did he do that!

[smartmummy]

Jamesbond:

My DS has scored 100 in Maths and 96 in Science for his SA2....I am very glad to share his marks with u all....The whole credit goes to Kiasuparents for the timely help in clearing all his doubts then and there. :grphug: ....My heartfelt thanks to all the parents.... :salute:


:thankyou:
:udawoman: :udaman:

wow! his hardwork paid off.Keep it up.

[kiasuMay11]

pchong:

Jamesbond:

My DS has scored 100 in Maths and 96 in Science for his SA2....I am very glad to share his marks with u all....The whole credit goes to Kiasuparents for the timely help in clearing all his doubts then and there. :grphug: ....My heartfelt thanks to all the parents.... :salute:


:thankyou:
:udawoman: :udaman:

Wow! How did he do that!

Think his mum put in lot of effort, too. Congrad

[pchong]

I must :udawoman:

[Happy Mama]

Jamesbond:

My DS has scored 100 in Maths and 96 in Science for his SA2....I am very glad to share his marks with u all....The whole credit goes to Kiasuparents for the timely help in clearing all his doubts then and there. :grphug: ....My heartfelt thanks to all the parents.... :salute:


:thankyou:
:udawoman: :udaman:

Wow :congrats: jamesbond! Excellent results and... 100 for Maths is FANTASTIC! :salute: