Complete number sentences involving multiplication and division by calculating missing numbers, eg find the missing numbers: 28 = ( ) x 7

1. Number detectives: *x4=12
2. Number detectives: *x5=15
3. Number detectives: *x4=12
4. Number detectives: 3x*=15
5. Number detectives: 4x*=40
6. Number detectives: 2x*=22
7. Number detectives: 5x*=30 5x*=35
8. Number detectives: ?x4=40
9. Number detectives: ?x2=12
10. Times Chain - ? x 6 = 12 x 2 = ?
11. Times Chain - ? x 5 = 20 x 3 = ?
12. Times Chain - ? x 2 = 8 x 6 = ?
13. Number Detectives: 3x?=12
14. Number Detectives: 6x?=36
15. Division chain - ? / 5 = 10 / 2 = ?
16. Division chain - ? / 2 = 6 / 3 = ?
17. Number detectives: ? / 10 = 5
18. Number detectives: ? / 5 = 7
19. Number detectives: 80 / ? = 40
20. Number detectives: 60 / ? = 20
21. Number detectives: 50 / ? = 5
22. Number detectives: ? / 8=90