2017 PSLE Math Question

Answer: 10 (Yes!) but why ?

…(see explanation here )

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Singapore Math (PSLE)

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This is the typical Singapore PSLE Math for 12-year-old school students sitting for Primary School Leaving Exams (PSLE).

The Primary 6 kids have not learnt Algebra, which will be taught only 1 year later in Secondary schools.

Singapore is proud of her unique “Singapore Math“, characterised by Polya-style Problem-Solving Process , aided with visual Modelling and Guesstimation techniques.

It is Singapore’s secret of being the World’s 2nd position in PISA Test (Math), after China (Shanghai) which beats us with Algebra teaching at this age.

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See if you can solve this problem without Algebra.

If stuck … (Answer below) …
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Singapore PSLE 2015 Math

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PSLE is “Primary School Leaving Exams” for 11~12 year-old children sitting at the end of 6-year primary education. The result is used as selection criteria to enter the secondary school of choice.

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Hint: Without seeing or feeling the weight of the $1 coin, you still can guess the answer. This is the essence of “Singapore Math” — using “Guesstimation“.

Answer (below):
Try before you scroll down.
If wrong answer, please go back to primary school 🙂
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Answer:

By elimination using ‘guesstimation’ method:
A) 6g too light,
D) 6 kg too heavy.
Left B & C…
C) 600 g > half kg for 8 coins ($1), not possible.

Ans: B = 60 g.

PSLE Maths

This is Singapore PSLE (Primary School Leaving Exams) Maths for 12- year-old kids.

It is not difficult for adults, but I wonder most kids have such analytical skill ?

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Answers below (scroll far behind….)
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(1)

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(2):
R – B = 1 for every suite of 5 cards
If R-B = 36
36×5= 180 cards