Problem Solving Heuristics for Lower Primary Mathematics

Yeap Ban Har

Catholic High School (Primary)

MATHEMATICAL PROBLEM SOLVING

The rationale of teaching mathematics is that it is “an excellent vehicle for the development

and improvement of a person’s intellectual competence”.

National Institute of Education

Wellington Primary School, Singapore

Ministry of Education Singapore 2006

an excellent vehicle for the development

and improvement of a person’s intellectual competence

“

”

mathematics

Move 3 sticks to get two squares.

Move 3 sticks to get two squares.

Wellington Primary School, Singapore

Wellington Primary School, Singapore

Wellington Primary School, Singapore

Wellington Primary School, Singapore

Wellington Primary School, Singapore

Wellington Primary School, Singapore

John had 1.5 m of copper wire. He cut some of the wire to bend into the shape shown in the figure below. In the figure, there are 6 equilateral triangles and the length of XY is 19 cm. How much of the copper wire was left? 

19 cm x 5 = 95 cm

150 cm – 95 cm = 55 cm

Example 1

F A M I L Y F A M I L Y F A M I L Y . . .

F A M I L Y F A M I L Y F A M I L Y . . . 6th 12th 18th

What is the 50th letter?

Example 2

104, 124, 144, 164, 184, . . .

104, 124, 144, 164, 184, 204, . . .

104, 124, 144, 164, 184, 204, 224, 244, 264,

Position

Number

1 10

2 12

3 14

4 16

5 18

… …

19 ?

Example 3

Even routine tasks such as finding the value of 7 x 9 are initially problems.

2 x 9 = 18

5 x 9 = 45

Primary Mathematics Standards Edition

Example 4

199 – 39 = 160

200 – 39 = ?

Example 5

17 + 19

17 + 19

16 + 20

Example 6

-

3

100- 97 3 101

- 98 3 102

- 99 3

-

5

100- 95 5 101

- 96 5 102

- 97 5

103- 98 5

104- 99 5

Children may do guess-and-check to get the solutions. Some children may observe a pattern / relationship. Guess-and-check and observe a pattern are

examples of heuristics.

Example 7

Khon Kaen, Thailand

4

1

5

23

Princess Elizabeth Primary School

Prin

cess E

lizabeth

Prim

ary

Sch

ool

Example 8

2 4 5

2xx 4xx 5xx

245254

425452

524542

Use a table is another problem-solving heuristic in mathematics.

Example 9

1

5 4

2

Example 10

A cupcake is sold at 40 cents each.How many cupcakes can be bought using $1 coin?

Example 11

A cupcake is sold at 40 cents each.How many cupcakes can be bought using $95?

Example 12

Ali has 3 picture cards.Janice has 2 more cards than Ali.How many picture cards do they altogether?

Ali

Janice

Ali has 19 picture cards.Janice has 12 more cards than Ali.How many picture cards do they altogether?

19Ali

Janice 12

Ali has 19 picture cards.Janice has 12 more cards than Ali.How many picture cards do they altogether?

19Ali

Janice 12

Example 13

Alan has 19 picture cards.He has 12 more cards than Bala.How many picture cards do they altogether?

19Alan

Bala 12

Example 14

Roy has some picture cards.Samantha has 12 more cards than Roy.They have 20 cards altogether.How many cards does Samantha have?

Roy

Samantha 1220