# Stage 4 whole numbers

## Strategies

Students can:

• express a number as a product of its prime factors
• find squares and square roots, cubes and cube roots

## Activities to support the strategies

### Activity 1

1. The teacher uses the factor tree to investigate the prime factors of numbers by dividing by prime numbers such as 2, 3, 5, 7, 11, 13 and so on.
2. Students use factor trees to determine the prime factors of 15, 27, 36, 72, 88, 100, 134, 210, 682, 526, 476, 24 960.

### Activity 2

Students:

• build models of square numbers using square tiles or graph paper. Students build models of cubic numbers using centicubes or draw cubic numbers using dot paper

3. Use calculators to determine squares, square roots, cubes and cubic roots, rounding to 2 decimal places where necessary: .

## References

### Australian curriculum

ACMNA150 Investigate and use square roots of perfect square numbers.

### NSW syllabus

MA4-9NA Operates with positive – integer and zero indices of numerical bases.