Divisibility TestPractise using the quick ways to spot whether a number is divisible by the digits 2 to 9. 
Tick boxes to show where the black number is exactly divisible by the red number.
If you are confident with this concept try the Delightfully Divisible challenge.
InstructionsTry your best to answer the questions above. Type your answers into the boxes provided leaving no spaces. As you work through the exercise regularly click the "check" button. If you have any wrong answers, do your best to do corrections but if there is anything you don't understand, please ask your teacher for help. When you have got all of the questions correct you may want to print out this page and paste it into your exercise book. If you keep your work in an ePortfolio you could take a screen shot of your answers and paste that into your Maths file. 



Transum.orgThis web site contains over a thousand free mathematical activities for teachers and pupils. Click here to go to the main page which links to all of the resources available. Please contact me if you have any suggestions or questions. 
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Mathematicians are not the people who find Maths easy; they are the people who enjoy how mystifying, puzzling and hard it is. Are you a mathematician? Comment recorded on the 26 March 'Starter of the Day' page by Julie Reakes, The English College, Dubai: "It's great to have a starter that's timed and focuses the attention of everyone fully. I told them in advance I would do 10 then record their percentages." Comment recorded on the 28 May 'Starter of the Day' page by L Smith, Colwyn Bay: "An absolutely brilliant resource. Only recently been discovered but is used daily with all my classes. It is particularly useful when things can be saved for further use. Thank you!" 
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Go MathsLearning and understanding Mathematics, at every level, requires learner engagement. Mathematics is not a spectator sport. Sometimes traditional teaching fails to actively involve students. One way to address the problem is through the use of interactive activities and this web site provides many of those. The Go Maths page is an alphabetical list of free activities designed for students in Secondary/High school. Maths MapAre you looking for something specific? An exercise to supplement the topic you are studying at school at the moment perhaps. Navigate using our Maths Map to find exercises, puzzles and Maths lesson starters grouped by topic.  
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If you found this activity useful don't forget to record it in your scheme of work or learning management system. The short URL, ready to be copied and pasted, is as follows: 
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A number is divisible by 2 if its last digit is even (0,2,4,6 or 8)
A number is divisible by 3 if the sum of its digits is divisible by 3.
A number is divisible by 4 if the number's last two digits are divisible by 4.
A number is divisible by 5 if its last digit is a 0 or 5.
A number is divisible by 6 if it is divisible by 2 and 3 (see rules above).
A number is divisible by 7 if 5 times the last digit added to the number made from the other digits is divisible by 7.
A number is divisible by 8 if the last three digits form a number that is divisible 8.
A number is divisible by 9 if the sum of the digits is divisible by 9.
A number is divisible by 10 if its last digit is 0.
A number is divisible by 11 if the alternating sum of its digits is divisible by 11. Alternating sum means ab+cd+... – m
A number is divisible by 12 if it is divisible by 3 and 4.
The projectable version of the divisibility tests can be found here: Divisibility Tests 212
There is a printable worksheet to go with this activity.
The divisibility test for 7 is thanks to a 12year old pupil, Chika Ofili, from Westminster School. You can read more about it here.
Answers to this exercise are available lower down this page when you are logged in to your Transum account. If you don’t yet have a Transum subscription one can be very quickly set up if you are a teacher, tutor or parent.
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Matrix simulation redesigned by Arunkumar Gudelli
Transum,
Saturday, October 27, 2018
"Type a four digit number on to your calculator. The keys used to type in this number must form a rectangle. Each digit should be one of the corners of this rectangle and you can work your way around this rectangle either clockwise or anticlockwise starting at any corner of the rectangle.
After you have created many fourdigit numbers using this method you should see that all of the numbers have something in common. They are all divisible by the same prime number. What is that prime number? "