The document details mathematical problems and solutions presented in a session on problem-solving at the National Institute of Education, Singapore. It includes various problems, such as calculating quantities with paper clips, arranging cards, and using digit tiles for addition and multiplication. Additionally, it discusses George Polya's problem-solving model and encourages reflection on the methods used for solving the presented problems.

1. singaporemathinactionSession 3mathematical problem solvingYeap Ban HarNational Institute of EducationSingaporewww.banhar.com

2. singaporemathinaction

3. singaporemathinactionProblem 1How many paper clips are there in the box on your table?

4. singaporemathinactionProblem 2Arrange the cards so that you can do the card trick shown to you.

5. singaporemathinactionProblem 3How many three-fourths are there in 1 whole?

6. Ateneo Grade School, ManilaHow many three-fourths are there in one whole?

7. singaporemathinaction-Problem 4Give a 3-digit number and a 2-digit number so that the difference is 3.3

8. singaporemathinaction+Problem 5Use one set of digit tiles to make a correct addition sentence.

9. singaporemathinaction+Problem 6Use one set of digit tiles to make a correct addition sentence.

10. singaporemathinactionxProblem 7Use one set of digit tiles to make a correct multiplication sentence.

11. Solutions from Participants45 x 2 = 90 18 x 2 = 36 16 x 3 = 48 43 x 2 = 8613 x 4 = 5217 x 2 = 3414 x 5 = 7026 x 3 = 7815 x 6= 9029 x 3 = 8734 x 2 = 6812 x 5 = 6013 x 6 =7835 x 2 = 7048 x 2 = 9616 x 5 = 8012x 8 = 9615 x 4 = 6019 x 2= 3827 x 3 = 8115 x 2 = 3017 x 4 = 6812 x 7 = 8419 x 3 = 57Why are there so few odd products?

12. Shaping MathsCoursebook 4A

13. singaporemathinaction614Two Numbers2 units  6144 units  1228The sum of the two numbers is 1228.Shaping MathsCoursebook 4A

14. singaporemathinactionboys34250girlsBoys & Girls2 units  342 – 50 = 2921 unit  292 ÷ 2 = 140 + 6 = 146There are 146 Primary Four boys.Shaping MathsCoursebook 4A

15. singaporemathinactionRavi1775 + 85SamuelStampsAfter1 unit  1860 ÷ 4 = 465At first, Samuel had 465 – 85 = 380 stamps.Shaping MathsCoursebook 4A

16. 1860160026024020Keys Grade School, Manila

17. singaporemathinactionGeorge Polya’sProblem-Solving Model Understand

18. Plan

19. Do

20. Look BacksingaporemathinactionCan you recall each of the four problem-solving phases when we were solving the problems in the last hour or so?Think!

21. singaporemathinactionWhat are some of the methods used to solve the problems? Make a list of heuristics used.Heuristics