Finding Prime & Composite Numbers using Divisibility Rules

These resources lay a solid foundation in the realm of mathematical learning, exploring alternative methods beyond standard algorithms in order to identify prime and composite numbers.

As an example instead of having to go through the standard algorithm of long division to determine whether a (large) number is divisible by e.g. 4 we actually only need to look at the last 2 digits in the number, and if they are divisible by 4 then the whole number is divisible by 4. 

In this resource pack student will have the opportunity to learn these shortcuts for numbers from 2 to 13.

Worksheets

The collection is divided into 3 separate sets:

• Divisibility Rules applied to Even Numbers: 4, 6, 8, and 12.

• Divisibility Rules applied to Odd Numbers: 7, 9, 11, and 13.

• Divisibility Rules applied to Prime Numbers: 2, 3, 5, and 7.

For each set of worksheets, you have the flexibility to select whether your students practice these rules with three-digit numbers, four-digit numbers, or five-digit numbers. 

How many worksheets are in each set ?

Lots and lots. At the click of a button all numbers are randomised, so the questions change every time.  This will allow you to create as many new worksheets you will need for practice throughout the year (classwork, homework, revision, fillers etc) or even give small groups of students in your class different sets of questions either at the same level or differentiated .

There will certainly be enough to ensure fluency in this topic. 

Answers found on the second page of every worksheet are automatically generated when you create a new worksheet.

Support for the Worksheets

Divisibility Guide

A brief overview of the worksheets and additional material

Divisibility Rules

This is designed for use by teachers to help explain the rules for each of the divisors from 2 to 13 with each rule accompanied by illustrative examples.

Divisibility A3 Poster

A3 colored Poster for display or as a memory jogger for students when needed.

Note
These resources are PDF documents and work with the official  Adobe Acrobat Reader on Windows or Mac computers with the randomising buttons also working via a touchscreen (PC or Mac)or on an Interactive Whiteboard.