This is the set of slides used at the seminar for Primary Five parents at Chongfu School in March 2011.

1. Help Your Child in Problem-Solving Heuristics Dr Yeap Ban Har banhar.yeap@pathlight.org.sg Marshall Cavendish Institute Singapore www.banhar.com Photo Credit: Students solving a mathematics problem using draw-a-diagram heuristic at Da Qiao Primary School.

3. Heuristics are rule of thumb that students can use to handle a problem when the solution is not obvious.

4. The problems used in the presentation are from PSLE Examination Questions Years 2006 – 2010 Mathematics published by Educational Publishing House Pte Ltd.

5. PSLE 2006 – 2010 Page 13 Question 45

10. Photo Credit: Primary 2 students at Woodlands Primary School using manipulatives to do multiplication and division.

11. PSLE 2006 – 2010 Page 13 Question 46 1.2 m x 42 = 50.4 m 43 – 6 = 37 There were 36 spacing 50.4 m ÷ 36 = 1.4 m The new spacing was 1.4 m.

13. PSLE 2006 – 2010 Page 19 Question 58 Guess when each tried taking 11 33 Last girl had 11 sweets 41 Last girl had 8 sweets 49 Last girl had 5 sweets 57 Last girl had 2 sweets

14. PSLE 2006 – 2010 Page 19 Question 58 List 1 List 2 11 + 6 22 + 6 33 + 6 44 + 6 55 + 6 66 + 6 16 + 25 24 + 25 32 + 25 40 + 25 48 + 25 56 + 25

15. PSLE 2006 – 2010 Page 19 Question 58 List 1 List 2 11 + 6 22 + 6 33 + 6 44 + 6 55 + 6 66 + 6 77 + 6 88 + 6 99 + 6 16 + 25 24 + 25 32 + 25 40 + 25 48 + 25 56 + 25 64 + 25 72 + 25 80 + 25

16. PSLE 2006 – 2010 Page 19 Question 58 3 x ? = 2 + 25 ? = 9 There were 10 girls. There were 9 x 11 + 6 = 8 x 10 + 25 = 105 sweets altogether.

17. PSLE 2006 – 2010 Page 19 Question 58 There were 10 girls. 11m + 6 = 8(m + 1) + 25 m = 9 Alternate Method 8n + 25 = 11(n – 1) + 6 n = 10

18. women 30 men There were 4 x 30 = 120 men and women at first.

19. Photo Credit: Primary 2 students at Woodlands Primary School using the interactive board to learn independently and collaboratively.

20. Method 1 Azlan, Bala, Chris, Darren Azlan, Bala, Chris, Enling Azlan, Bala, Darren, Enling Azlan, Chris, Darren, Enling Bala, Chris, Darren, Enling, Method 2 Selecting 4 persons from a group of 5 is the same as to leave out one person from a group of 5. There are 5 ways to leave out 1 person from a group of 5. Hence there are 5 ways to select 4 prefects from a group of 5 students.

21. 1 third = 4/12 remainder = 5/12 1 fourth = 3/12 38 + 57 = 95 2 fifths  38 peaches 2 fifths  38 peaches 1 fifth  19 peaches 3 fifths  3 x 19 pears = 57 pears 5/12  95 fruits 1/12  19 fruits There were 12 x 19 fruits or 228 fruits.