Divisibility rules
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This document outlines divisibility rules for numbers 2 through 12. For each number, it provides an example number to divide by that number and explains why the number is divisible based on the rule. The rules are: for 2, the number is divisible if the last digit is even; for 3, the digits sum is divisible by 3; for 4, the last two digits are divisible by 4; for 5, the last digit is 0 or 5; for 6, it is divisible by both 2 and 3; for 7, applying a doubling and subtracting rule on the last digit; for 8, the last three digits are divisible by 8; for 9, the digits sum is divisible by 9; for 10, the last digit
Divisibility rules
- 2. DIVISIBILTY RULES FOR NUMBERS A. 2 B. 3 C. 4 D. 5 E. 6 F. 7 G. 8 H. 9 I. 10 J. 11 K. 12
- 3. Division rule for number “2” RULE ANALYSIS 1. A number is divisible by 2 if the last digit is 0,2,4,6 or 8. 1. Example-9168 /2=4584 2. 9168 is divisible by 2 as the last digit is 8.
- 4. Division rule for number “3” RULE ANALYSIS 1. A number is divisible by 3 if the sum of the digits is divisible by 3. 1. Example-9168 /3=3056 2. 9168 is divisible by 3 since the sum of the digits is 24. (9+1+6+8=24), and 24 is divisible by 3.
- 5. Division rule for number “4” RULE ANALYSIS 1. A number is divisible by 4 if the number formed by the last 2 digits is divisible by 4. 1. Example-9168 /4=2292 2. 9168 is divisible by 4 as the last two digits form the number 68 and it is divisible by 4.(17 X 4=68)
- 6. Division rule for number “5” RULE ANALYSIS 1. A number is divisible by 5 if last digit is 0 or 5. 1. Example-9170 /5=1834 2. 9170 is divisible by 5 as the last digit is 0.
- 7. Division rule for number “6” RULE ANALYSIS 1. A number is divisible by 6 if it is divisible by 2 and 3. 1. Example-9168 /6=1528 2. Example-9168 /2=4584 3. Example-9168 /3=3056 4. So 9168 is divisible by 6 as it is divisible by 2 and 3*. *If you forgot how it is divisible by 6, see here .
- 8. Division rule for number “7” RULE ANALYSIS 1. Take the last digit off the number 2. Double it 3. Subtract the doubled number from the remaining number. 4. If the result is divisible by 7, then the number is divisible by seven. 1. Example-7168 /7=1024 2. 7168 3. 8x2=16 4. 716-16=700 5. 700 is divisible by 7
- 9. Division rule for number “8” RULE ANALYSIS 1. A number is divisible by 8 if the last 3 digits are divisible by 8. 1. Example- 9168 /8=1146 2. 9168 is divisible by 8 as the last 3 digits(168) is divisible by 8(168 when divided by 8 is 21).
- 10. Division rule for number “9” RULE ANALYSIS 1. Find the sum all the digits. 2. Check whether the digits are divisible by 9. 1. Example- 9171/9=1019 2. 9171 is divisible by 9 as the sum of the digits (9+1+7+1=18) and 18 is divisible by 9.
- 11. Division rule for number “10” RULE ANALYSIS 1. Check that last number is zero. 1. Example- 9170 /10=917 2. 9170 is divisible by 10 as the last number is zero.
- 12. Division rule for number “11” RULE ANALYSIS 1. According to the divisibility rule of 11, we must subtract. 2. Add the digits in odd places. 3. Add the digits in even places. 4. Find difference between both of them. 5. If answer is either 0 or divisible by 11, then it is divisible 1. Example-10813 /11=983 2. 10813 3. Odd place sum=1+8+3=12 4. Even place sum=0+1=1 5. Difference=12-1=11
- 13. Division rule for number “12” RULE ANALYSIS 1. A number is divisible by 12 if it is divisible by both 3 and 4. 1. Example -2424/12=202 2. 2+4+2+4=12 divisible by 3 3. Last two digit is 24 and it is divisible by 4.