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Original Title: Highlights in Past Years' PSLE Maths

I have heard that the PSLE questions published commercially do not always contain the past years' challenging questions. I hoped that by creating this thread we can consolidate the "highlights" over the years so that this will be a resource for each year's parents in their quest to prepare their children for PSLE maths.

2000 (1st year I know of with an uproar)

What is the last digit of the sum 1 + 2 + 3 + ... + 5 + 96 + 97

Ans : 3

After 2000, every schoolkid should have been taught how to do this question by p6. Therefore such questions no longer pose a threat unless...

__ __ __ ___ B

|__|__|__|__| North

|__|__|__|__| -->East

|__|__|__|__|

A

How many ways are there to get from point A (bottom left corner) to point B (top right) if you are only allowed to move an odd number of steps northwards(up) each time and an even number of steps eastwards (right) each time.

Ans: 4

This is similar to those kinda "route/path finding" questions experienced by students in maths competitions or exams, but there is a significant difference in the underlying math concept. The conventional path finding questions involve no restrictions on restrictions by passing through certain points.

Given this small size, the answer is likely to be small, therefore students are better off brute-forcing, as the mathematical working required to deduct logically all possible routes is too time-consuming and probably beyond the average student.

When the famous Andrew Er's Challenging Problems was published in 2001, he posed a similar problem too.

A squarish grid, 6 squares across, 6 squares down, seeking the number of ways from X (the top left hand corner) to Y (bottom right hand corner) if only allowed to move an even number of steps southwards (at a time) and an odd number of step eastwards (at a time).

Answer given in the book : 5

The present's edition contained a similar but simplified version.

Trivia : These 2 PSLE questions were posed to 5 presidents of international MENSA associations (whose combined IQ exceeds 800) and Mr Robert Beaty (president of American Mensa) solved the first problem in 15 secs and took more than 4 mins to answer the second one.

Parents complained that the questions require higher-order thinking skills not taught.

2005

http://www.math.nus.edu.sg/aslaksen/papers/PSLE2005.pdf

Here you can see the infamous question 13 (the flawed question).

2007

http://sc-math.com/math-talk/math-psle07.php

http://kofplayer.wordpress.com/2007/10/ ... -too-hard/

2008

http://www.jamesangtutors.com/forum/vie ... 9288b33365

http://psle2008.blogspot.com/2008/10/qu ... ual-5.html

2009

http://psle2009.blogspot.com/2009/10/ps ... tions.html

For our own community's discussion and numerous solutions view the psle 2009 maths thread

http://www.kiasuparent.com/kiasu/forum/ ... php?t=5906

Miscellaneous

http://www.amt.canberra.edu.au/icmis16psinyeap.pdf

This contains some psle questions published by the SEAB, worth a look.

If anyone else has any idea(perhaps you did a newspaper cutting ) about other questions in 2005 or whether theres any uproar in the years 2002-2004 feel free to add on.[/img]

## Q&A - PSLE Maths - Highlights ONLY

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