Q&A - PSLE Math

[Dharma]

kancheongmum:

Hi Tianzhu and VC mum tks finally understand the solutions now. But still cannot understand the model solution posted by pecalis on the vanilla and chocolate questions. Is ok my ds is not good with model. Need help in this question Maha BodhiQ6 (Ans $12)

each apple cost 40cts each pear cost 60 cts
Mrs Gopal and Mrs Ari went to the supermarket. Both women decided to spend all their money on either apples or pears and they would not buy the same fruit. If Mrs Gopal bought only pears, she would have 9 more fruits than Mrs Ari. If she bought only apples, she would have 41 more fruits than Mrs Ari. How much more money has Mrs Gopal than Mrs Ari?

Thank you

1u/60 - 1p/40 = 9
1u/40 - 1p/60 = 41
5u/120 - 5p/120 = 50

Diff in amt of money Mrs Gopal and Mrs Ari had = 1u - 1p
1u - 1p = 10 x 120 = 1200 cents = $12

[tianzhu]

kancheongmum:

Is ok my ds is not good with model.

Hi kancheongmum

If you decide to see MD solution on vanilla and chocolate question, just let me know.

Best wishes

[tianzhu]

kancheongmum:

Need help in this question Maha BodhiQ6 (Ans $12)

each apple cost 40cts each pear cost 60 cts
Mrs Gopal and Mrs Ari went to the supermarket. Both women decided to spend all their money on either apples or pears and they would not buy the same fruit. If Mrs Gopal bought only pears, she would have 9 more fruits than Mrs Ari. If she bought only apples, she would have 41 more fruits than Mrs Ari. How much more money has Mrs Gopal than Mrs Ari?

Hi kancheongmum

This question is quite new trend, can’t recall seeing it in past years papers previously.

An interesting one.The key to unlock this question is to note that the amount of money held buy Mrs Gopal and Mrs Ari remains the same in both scenarios.

Best wishes

[kancheongmum]

tianzhu:

kancheongmum:

Is ok my ds is not good with model.

Hi kancheongmum

If you decide to see MD solution on vanilla and chocolate question, just let me know.

Best wishes

Hi Tianzhu always know you are so helpful. Ok pls let everyone see the MD solution especially the beautiful graphics. tks

[kancheongmum]

tianzhu:

kancheongmum:

Need help in this question Maha BodhiQ6 (Ans $12)

each apple cost 40cts each pear cost 60 cts
Mrs Gopal and Mrs Ari went to the supermarket. Both women decided to spend all their money on either apples or pears and they would not buy the same fruit. If Mrs Gopal bought only pears, she would have 9 more fruits than Mrs Ari. If she bought only apples, she would have 41 more fruits than Mrs Ari. How much more money has Mrs Gopal than Mrs Ari?

Hi kancheongmum

This question is quite new trend, can’t recall seeing it in past years papers previously.

An interesting one.The key to unlock this question is to note that the amount of money held buy Mrs Gopal and Mrs Ari remains the same in both scenarios.

Best wishes

Hi VC mum and Tianzhu,

After reading Tianzhu post, lead me to solve this question using this method which is not new. The question of Tom spend $40 per day and Mary spend $80 per day and Mary would have $500 left when Tom has spent all his money .......

Apples : Pears ---- 40:60 ---- 2:3

1st case Ari spent 2/3 of Gopal 2nd case Ari spent 3/2 of Gopal
equal fraction 2/3 = 6/9 and 3/2 = 6/4

Gopal ()()()()()()()()() $5.40
Ari ()()()()()()

Gopal ()()()() $16.40
Ari ()()()()()()


9u + $5.40 = 4u + $16.40
5u ---- $11
1u ---- $2.20
Gopal money more than Ari by ---- 3u + $5.40 = (3 x $2.20) + $5.40
= $12

[tianzhu]

Hi kancheongmum


I am very impressed by your ability to adapt familiar techniques to newer trend types of questions. I learn an alternative way to solve this question from you today.

Perhaps you may want to try to solve the vanilla and chocolate question with MD.

Start with 40% = 4/10 = 2/3.

Consider for the first case, the ratio is 2:3.For the second case, the ratio is 3:7.

Using equivalent ratios, change to (23) and (32) as the number of vanilla sweets is the same at both cases.

To start, the first model is 3u+10 + 3u +10 for vanilla sweets.

Best wishes

[firebird]

Dear Dharma & Tianzhu sirs


Good afternoon.

My son is talking his PSLE this year. I am helping him with the guidance from this forum.

His SA1 2010 Maths mark was 70. Preliminary 2010 maths mark was 85.

Like all parents I would want to assist my child to improve his maths further. Time is limited on top of managing to improve other 3 subjects.

The school and we at home (with the help from this forum), have gone through about 10 to 13 schools Preliminary 2009 maths papers, which i am still keeping.

I seek your guidance to help my son’s maths practice from now to PSLE. I have already purchased the 10 sets of 2010 Preliminary maths papers from other schools.

Please help me.

Thank you.
Firebird

[Dharma]

firebird:

Dear Dharma & Tianzhu sirs


Good afternoon.

My son is talking his PSLE this year. I am helping him with the guidance from this forum.

His SA1 2010 Maths mark was 70. Preliminary 2010 maths mark was 85.

Like all parents I would want to assist my child to improve his maths further. Time is limited on top of managing to improve other 3 subjects.

The school and we at home (with the help from this forum), have gone through about 10 to 13 schools Preliminary 2009 maths papers, which i am still keeping.

I seek your guidance to help my son's maths practice from now to PSLE. I have already purchased the 10 sets of 2010 Preliminary maths papers from other schools.

Please help me.

Thank you.
Firebird

Hi firebird,

You can always put up the questions that your son is uncertain about; either the workings/ approach and any one of the many problem solvers we have in this forum will chip to help out.

It is nice to hear that your son has made a remarkable improvement from SA1 to Prelims. Keep up the good work!

Best regards.

[firebird]

Dear Mr Dharma


Thanks for the reply.

Could you please let me know where i could focus now:

1) Try again those sums that my son got wrong previously

or

2) Try to finish all the 2010 preliminary school papers ( school has done 2 to date)

or

3) Select new questions similar to those that my son makes mistakes from assessment books. If so could you recommend a book or two.

Please help.

Many thanks
firebird

[tianzhu]

Hi firebird


First, we are happy to hear about your son’s remarkable improvement in his maths marks.

Many of the last few questions (4/5 marks types) in the recent preliminary maths examination have been posted and solved in some online forums including KSP.

Should your boy meets any difficulties in his revision, we’ll be happy to help. Please feel free to post your questions; you’ll certainly get help from some of the volunteers here.

Best wishes