Number patterns

 

 

Complete the number sequences…
​What is the rule for each sequence??

Example:

3, 6, 9, 12, 15, 18, 21, 24. Rule: Add 3

8, 12, 16, _, _, _​ Rule:
2. 19, 28, 37, _, _, _ ​Rule:
3. 33, 27, 21, _, _, _ ​Rule:
4. 13, 25, 37, _, _, _​ Rule:
5. 100, 96, 92, _, _, Rule:
6. 43, 38, 33, _, _, _ ​Rule:
7. 74, 82, 90, _, _, _​Rule:
8. 62, 65, 68, _, _, _​Rule:
9. 2, 20, 38, _, _, _​ Rule:
10. 66, 60, 54, _, _, _​Rule:
11. _, _, 44, 33, 22, _​Rule:
12. _, 40, 60, 80, _, _​Rule:
13. _, _, _, 49, 42, 35​ Rule:
14. _, _, 90, 81, 72, _​ Rule:
15. _, _, -5, 0, 5, _​ Rule:
16. _, -8, -4, 0, _ _​ Rule:
17. 85, _, 77, 73, _, _​Rule:

 
Extension: Make up three number sequences for someone else to solve. One easy, one medium and one hard.

Can you crack this code?

http://www.primaryresources.co.uk/maths/powerpoint/code_crackers.ppt20140313-212546.jpg