2011 PSLE Discussions and Strategy

[James Ang]

This question is from a neighbourhood school prelims.


P6 Math
Leslie bought some sweets and gave 2/3 of it to Alan. Alan bought some chocolates and gave 2/3 of it to Leslie. Leslie ate 6 chocolates and Alan ate 6 sweets. The ratio of Leslie’s chocolates to sweets become 2:1 and the ratio of Alan’s chocolates to sweets is 4:5. How many chocolates did Alan buy? (5 marks)

[Verysuperkiasu]

James Ang:

This question is from a neighbourhood school prelims.


P6 Math
Leslie bought some sweets and gave 2/3 of it to Alan. Alan bought some chocolates and gave 2/3 of it to Leslie. Leslie ate 6 chocolates and Alan ate 6 sweets. The ratio of Leslie's chocolates to sweets become 2:1 and the ratio of Alan's chocolates to sweets is 4:5. How many chocolates did Alan buy? (5 marks)

What's the answer?

[James Ang]

Someone asked me the question.


My answer is 48 chocolates. Solved by drawing models.

[Pen88n]

James Ang:

This question is from a neighbourhood school prelims.


P6 Math
Leslie bought some sweets and gave 2/3 of it to Alan. Alan bought some chocolates and gave 2/3 of it to Leslie. Leslie ate 6 chocolates and Alan ate 6 sweets. The ratio of Leslie's chocolates to sweets become 2:1 and the ratio of Alan's chocolates to sweets is 4:5. How many chocolates did Alan buy? (5 marks)

Exactly like one of the past year PSLE question - just change the fraction and ratio numbers. Easiest to solve by modelling.

[James Ang]

Only 2 students got it right in the school prelims.

[Pen88n]

James Ang:

Only 2 students got it right in the school prelims.

Usually under normal circumstances and the kid has been exposed to this question before, they can do, Under prelim sometimes stress, so they may be a little panicky or careless, or misinterpret some info, and ended up losing some marks.

[SAplayer]

James Ang:

This question is from a neighbourhood school prelims.


P6 Math
Leslie bought some sweets and gave 2/3 of it to Alan. Alan bought some chocolates and gave 2/3 of it to Leslie. Leslie ate 6 chocolates and Alan ate 6 sweets. The ratio of Leslie's chocolates to sweets become 2:1 and the ratio of Alan's chocolates to sweets is 4:5. How many chocolates did Alan buy? (5 marks)

Easy question de...
Here is the solution by ratio + simple algrbra:

Let the number of chocolates bought =x
Let the number of sweets bought =y
2(1/3y) = 2/3 x-6 --------equation 1
4(2/3 y-6) = 5(1/3 x) ---------equation 2
From equation 1,
2y = 2x -18 --------------- equation 3
From equation 2,
8y -72 = 5x ---------------- equation 4

Substitute equation 3 into equation 4
4(2x -18) -72 = 5y
8x -72 -72 = 5x
3x = 144
X = 48
Therefore, the number of chocolates bought by Alan is 48.

[PiggyLalala]

James Ang:

This question is from a neighbourhood school prelims.


P6 Math
Leslie bought some sweets and gave 2/3 of it to Alan. Alan bought some chocolates and gave 2/3 of it to Leslie. Leslie ate 6 chocolates and Alan ate 6 sweets. The ratio of Leslie's chocolates to sweets become 2:1 and the ratio of Alan's chocolates to sweets is 4:5. How many chocolates did Alan buy? (5 marks)

Just curious to know,
How did your dd/ds solve the above question? model or algebra?
Also how many of your dd/ds solve all the maths questions by model only? Do you teach them solve by algebra?
Hope to hear from the parents here. Thank you.

All the best to your DD/DS in the coming PSLE.

[hashroop]

I have not receive the papers from Jeremy yet. He said was going to be yesterday. I will call him again.

[Brenda10]

hashroop:

I have not receive the papers from Jeremy yet. He said was going to be yesterday. I will call him again.

Hi hashroop,

Hopefully you can recd today!