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| − | === 2: Last Digit Must Be Even ===
| + | #REDIRECT[[Divisibility rules]] |
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| − | Let ABCDEF be a 6-digit number. Note the value of "ABCDEF" is:
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| − | <math>100000A + 10000B + 1000C + 100D + 10E + F</math>
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| − | OR <math>2(50000A + 5000B + 500C + 50D + 5E) + F</math>
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| − | If F is divisible by 2 (i.e. is 2, 4, 6, 8, or 0), then so is the number "ABCDEF"
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| − | === 3: Three Divides The Sum Of The Digits ===
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| − | Let ABCDEF be a 6-digit number. Note the value of "ABCDEF" is:
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| − | <math>100000A + 10000B + 1000C + 100D + 10E + F</math>
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| − | OR <math>99999A + 9999B + 999C + 99D + 9E + A + B + C + D + E + F</math>
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| − | OR <math>3(33333A + 3333B + 333C + 33D + 3E) + A + B + C + D + E + F</math>
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| − | If A + B + C + D + E + F is divisible by 3, then so is ABCDEF.
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| − | === 4: Last TWO Digits Must Be Divisible by 4 ===
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| − | Let ABCDEF be a 6-digit number. Note the value of "ABCDEF" is:
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| − | <math>100000A + 10000B + 1000C + 100D + 10E + F</math>
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| − | OR <math>4(25000A + 2500B + 250C + 25D) + 10E + F</math>
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| − | If "EF" is divisible by 4, then so is the number "ABCDEF"
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| − | === 5: Last Digit Must Be 0 or 5 ===
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| − | Let ABCDEF be a 6-digit number. Note the value of "ABCDEF" is:
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| − | <math>100000A + 10000B + 1000C + 100D + 10E + F</math>
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| − | OR <math>5(20000A + 2000B + 200C + 20D + 2E) + F</math>
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| − | If F is divisible by 5 (i.e. is 0 or 5), then so is the number "ABCDEF"
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| − | === 8: Last THREE Digits Must Be Divisible by 8 ===
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| − | Let ABCDEF be a 6-digit number. Note the value of "ABCDEF" is:
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| − | <math>100000A + 10000B + 1000C + 100D + 10E + F</math>
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| − | OR <math>8(12500A + 1250B + 125C) + 100D + 10E + F</math>
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| − | If "DEF" is divisible by 8, then so is the number "ABCDEF"
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| − | === 9: Three Divides The Sum Of The Digits ===
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| − | Let ABCDEF be a 6-digit number. Note the value of "ABCDEF" is:
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| − | <math>100000A + 10000B + 1000C + 100D + 10E + F</math>
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| − | OR <math>99999A + 9999B + 999C + 99D + 9E + A + B + C + D + E + F</math>
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| − | OR <math>9(11111A + 1111B + 111C + 11D + E) + A + B + C + D + E + F</math>
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| − | If A + B + C + D + E + F is divisible by 9, then so is ABCDEF.
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