Divisibility Mathematics 5

This power point presentation is for 5th graders.

1. DIVISIBILTY

2. WHAT IS DIVISIBILITY? It means if you divide one number by another, the result is a whole number WITHOUT a remainder. EXAMPLES: 12 ÷ 6 = 2 No remainder 15 ÷ 5 = 3 No Remainder

3. DIVISIBILITY RULE: If the number is even, that is, the number ends with 0, 2, 4, 6, or 8, then the number is divisible by 2. 46 912 354 2960 They are all divisible by 2.

4. DIVISIBILITY RULE: If a number ends with 0 or 5, then the number is divisible by 5. 600 805 2630 235 They are all divisible by 5 because their last digits are either 0 or 5.

5. DIVISIBILITY RULE: If the ones digit of a number is zero, then the number is divisible by 10. 600 890 2120 130 They are all divisible by 10 because their last digits are 0.

6. DO THIS IN YOUR NOTEBOOK!

7. Complete the chart. Write D on the appropriate space if the given number is divisible by the number in the top row, or N if it is not. 2 5 10 92 640 D D D 45 835 N D N 92 724 D N N 45 678 D N N 94 136 D N N 245 648 D N N 802 185 N D N 914 000 D D D 48 360 472 D N N 65 927 640 D D D

8. DIVISIBILITY RULE: To determine if a number is divisible by 3, add the digits of the number. If the sum of the digits is divisible by 3, then the number is divisible by 3. 3 Example: 6 312 6 + 3 + 1 + 2 = 12 12 divided by 3 is 4, so 6312 is divisible by 3 .

9. Example: 27 531 2 + 7 + 5+3+1 = 18 18 divided by 3 is 6, so 27 531 is divisible by 3 . LETS HAVE A TRY ! Is 4284 divisible by 3? Is 2293 divisible by 3? Is 7689 divisible by 3? Is 7726 divisible by 3? YES NO YES NO

10. Identify the numbers divisible by 3. Yes or No 562 2. 444 3. 432 4. 491 5. 127 NO YES YES NO NO

11. DIVISIBILITY RULE: 6 A number is divisible by 6 if it is even and the sum of the digits is divisible by 3. In short, the number must be divisible by both 2 and 3. Example: 234 780 The number 234,780 is an even number. 2+3+4+7+8+0 = 24 (24 is divisible by 3)

12. LETS HAVE A TRY ! Is 25270 divisible by 6? Is 26476 divisible by 6? Is 44412 divisible by 6? Is 56412 divisible by 6? YES NO NO YES

13. Identify the numbers divisible by 6. Yes or No 773 2. 816 3. 945 4. 162 5. 336 NO YES NO YES YES

14. DIVISIBILITY RULE: 9 A number is divisible by 9 if the sum of its digits is a multiple of 9. Example: 162 1 + 6 + 2 = 9 (9 is in the multiplication table of 9) Therefore 162 is divisible by 9.

15. LETS HAVE A TRY ! Is 12 917 divisible by 9? Is 18315 divisible by 9? Is 39918 divisible by 9? Is 42619 divisible by 9? NO YES NO NO

16. Yes or No 342 2. 904 3. 201 4. 621 5. 225 Identify the numbers divisible by 9. YES NO NO YES YES

17. DIVISIBILITY RULE: A number is divisible by 4 if the number formed by its last two digits is divisible by 4 or if the last two digits are zeros. Example: 216 The last two digits which is 16 is divisible by 4.

18. LETS HAVE A TRY ! Is 95 632 divisible by 4? Is 672 divisible by 4? Is 9918 divisible by 4? Is 1600 divisible by 4? YES YES NO YES

19. DIVISIBILITY RULE: A number is divisible by 8 if the number formed by its last three digits is divisible by 8, or if the last three digits are zeros. Example: 7 136 The last three digits which is 136 is divisible by 8, then 7136 is divisible by 8.

20. LETS HAVE A TRY ! Is 19 640 divisible by 8 ? Is 9 312 divisible by 8 ? Is 464 divisible by 8 ? Is 18 000 divisible by 8 ? YES YES YES YES

21. DIVISIBILITY RULE: A number is divisible by 12 if the sum of the digits is a multiple of 3 and the last two digits are zeros or form a number that is a multiple of 4.In short a number is divisible by 12 if it is divisible by both 3 and 4. Example: 3 936 3+9+3+6 = 21, which is divisible by 3 36, which is divisible by 4 So the number 3936 is divisible by 12

22. LETS HAVE A TRY ! Is 375 divisible by 12? Is 729 divisible by 12? Is 432 divisible by 12? Is 756 divisible by 12? NO NO YES YES

23. DIVISIBILITY RULE: STEP 1: Add the odd- positioned digits starting from the left. Ex. 4 6 3 4  4+6+4 =14 STEP 2: Add the even- positioned digits starting from the left. Ex. 4 6 3 4  3 +0= 3 STEP 3: Subtract the sums in this manner: the greater sum minus the lesser sum. Ex. 14 – 3 = 11

24. If the difference is 0 or multiple of 11, then the given numbers is divisible by 11. 1 8 1 3  3 + 8 + 1= 12 Ex. 10 813 1 8 1 3  1 + 0 = 1 12 – 1 = 11 YES

25. LETS HAVE A TRY ! Is 495 divisible by 11? Is 9835 divisible by 11? Is 14 806 divisible by 11? Is 918 291 divisible by 11? YES NO YES YES