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To find if a number is divisible by 2
Check to see if the number is even.
It must end in a 0, 2, 4, 6, or 8. You try! Is 33 divisible by 2? yes no Rule for 2 94 is even since ends in a 4 Is 94 divisible by 2? Yes 94 is divisble by 2!
To find if a number is divisible by 3
Check to see if the sum of the digits is divisible by 3. You try! Is 33 divisible by 3? yes no Rule for 3 Since 9+4=13 and 13 is not evenly divisible by 3, 94 is not evenly divisible by 3 Is 94 divisible by 3? To find if a number is divisible by 4
Check to see if the last 2 digits are divisible by 4. You try! Is 142 divisible by 4? yes no Rule for 4 The last two digits are 20.
Since 20 is divisible by 4 120 is divisible by 4. Is 120 divisible by 4? To find if a number is divisible by 5
Check to see if the last digit is a 0 or 5. You try! Is 241 divisible by 5? yes no Rule for 5 Since the last digit is a 0, 120 is divisible by 5. Is 120 divisible by 5? To find if a number is divisible by 6
Check to see if it is divisible by both 2 and 3. You try! Is 246 divisible by 6? yes no Rule for 6 Since 126 is even it is divisible by 2.
Since 1+2+6=9 and 9 is divisible by 3, 126 is divisible by 3.
Since 126 is divisible by both 2 and 3 it is also divisible by 6. Is 126 divisible by 6? To find if a number is divisible by 8
Check to see if the last 3 digits are divisible by 8. You try! Is 808 divisible by 8? yes no Rule for 8 The last 3 digits are 888.
Since 888 is divisible by 8, 2,888 is divisible by 8. Is 2,888 divisible by 8? To find if a number is divisible by 9
Check to see if the sum of the digits is divisible by 9. You try! Is 234 divisible by 9? yes no Rule for 9 Since 1+4+4=9 and 9 is divisible by 3, 144 is evenly divisible by 9. Is 144 divisible by 9? To find if a number is divisible by 10
Check to see if the last digit is a 0. You try! Is 2401 divisible by 10? yes Rule for 10
no Since the last digit is a 0, 120 is divisible by 10. Is 120 divisible by 10? To find if a number is divisible by 11
Alternately subtract then add digits. If result is divisible by 11 then so i2 the original number You try! Is 63,219,619,914 divisible by 11? yes Rule for 11
no Since 4-5+6-8+2-1+0-9=11 this number is divisible by 11 Is 45,682,109 divisible by 11? To find if a number is divisible by 12
Check divisibility rules for 3 and 4 (3 X 4 = 12) You try! Is 263,240divisible by 10? yes Rule for 12
no Since the sum of the digits is 3 then it's divisible by 3. Since 20 is divisible by 4 it's divisible by 4. Since both rules apply it's divisible by 12. Is 120 divisible by 12? Is 7890 divisible by: 2 4 5 3 Answer yes or no. Is 4,316,280,948 divisible by: 2 5 6 3 4 Answer yes or no. 8 9 10 11 12 Is 8,456,159,112 divisible by: 2 5 6 3 4 Answer yes or no. 8 9 10 11 12 Is 34,488,115,200 divisible by: 2 5 6 3 4 Answer yes or no. 8 9 10 11 12 Is 17,570,710,080 divisible by: 2 5 6 3 4 Answer yes or no. 8 9 10 11 12 Is 7,460,453,801,339 divisible by: 2 5 6 3 4 Answer yes or no. 8 9 10 11 12 |