Divisibility Test for 2, 4 and 8
A number is divisible by 2, if its last digit is divisible by 2. For instance 26, 38 etc.
A number is divisible by 4, if the number formed by its last two digits is divisible by 4.
For example, 168.
68 is the number formed by last 2 digits of 168.
Since 68 is divisible by 4, 168 would also be divisible by 4.
Likewise, 1236 would be divisble by 4 since 36 is divisible by 4
A number is divisible by 8 if the number formed by its last three digits is divisible by 8. For example, 1632.
Since 632 is divisible by 8, 1632 would also divisible by 8.
Division by 3 and 9
A number is divisible by 3 if the sum of its digits is divisible by 3.
For example, 24.
Sum of 2 and 4 is 6.
6 is divisible by 3
So 24 would also be divisible by 3
Similarly, 108
Sum of 1, 0 and 8 is 9.
9 is divisible by 3.
Hence, 108 would also be divisible by 3
A number is divisible by 9 if the sum of its digits is divisible by 9.
For example, 36.
Sum of 3 and 6 is 9 which is obviously divisible by 9. Hence 36 would also be divisble by 9.
Similarly, 189.
1 + 8 + 9 = 18.
18 is divisible bh 9.
So 189 would also be divisible by 9
Division by 6
If a number is divisible by 3 as well as by 2, then it would be divisible by 6.
For example, 36. It is divisible by 2 as well as 3. Hence, 36 would be divisble by 6 too.
Division by 5 and 10
A number is divisible by 5 if its last digit is 5 or 0 (e.g. 435,280).
A number is divisible by 10 if its last digit is O (e.g. 390, 2000).
Division by 11
Find the sum of the digits in the even places and the sum of the digits in the odd places. If the differences between the two sums is 0 or a multiple of 11, then the given number would be divisible by 11
For example, 72545.
Digits in odd places - 7,5,5. Sum of these digits is 17
Digits in even places - 2,4. Sum of these 2 digits is 6.
Difference between both the sums = 17 - 6 = 11. Thus sum is divisible by 11. Hence 72545 would be divisible by 11.
A number is divisible by 2, if its last digit is divisible by 2. For instance 26, 38 etc.
A number is divisible by 4, if the number formed by its last two digits is divisible by 4.
For example, 168.
68 is the number formed by last 2 digits of 168.
Since 68 is divisible by 4, 168 would also be divisible by 4.
Likewise, 1236 would be divisble by 4 since 36 is divisible by 4
A number is divisible by 8 if the number formed by its last three digits is divisible by 8. For example, 1632.
Since 632 is divisible by 8, 1632 would also divisible by 8.
Division by 3 and 9
A number is divisible by 3 if the sum of its digits is divisible by 3.
For example, 24.
Sum of 2 and 4 is 6.
6 is divisible by 3
So 24 would also be divisible by 3
Similarly, 108
Sum of 1, 0 and 8 is 9.
9 is divisible by 3.
Hence, 108 would also be divisible by 3
A number is divisible by 9 if the sum of its digits is divisible by 9.
For example, 36.
Sum of 3 and 6 is 9 which is obviously divisible by 9. Hence 36 would also be divisble by 9.
Similarly, 189.
1 + 8 + 9 = 18.
18 is divisible bh 9.
So 189 would also be divisible by 9
Division by 6
If a number is divisible by 3 as well as by 2, then it would be divisible by 6.
For example, 36. It is divisible by 2 as well as 3. Hence, 36 would be divisble by 6 too.
Division by 5 and 10
A number is divisible by 5 if its last digit is 5 or 0 (e.g. 435,280).
A number is divisible by 10 if its last digit is O (e.g. 390, 2000).
Division by 11
Find the sum of the digits in the even places and the sum of the digits in the odd places. If the differences between the two sums is 0 or a multiple of 11, then the given number would be divisible by 11
For example, 72545.
Digits in odd places - 7,5,5. Sum of these digits is 17
Digits in even places - 2,4. Sum of these 2 digits is 6.
Difference between both the sums = 17 - 6 = 11. Thus sum is divisible by 11. Hence 72545 would be divisible by 11.
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