Prime Factorization Using Divisibility Rules
You can use the divisibility rules to help you find the
prime factorization of larger numbers.
Find the prime factorization and write in exponential form.
- 32 13. 24 14. 50 15. 125 16. 63
- 71 18. 44 19. 60 20. 100 21. 96
Find the prime factorization of 9450.
ends in 0; divide by 10
digit sum is 18; divide by 9
ends in 5; divide by 5
digit sum is 3; divide by 3
all prime numbers
So, the prime factorization of 9450 is 2 33 52 7.
9
945
21
9450
2 5 3 3 5
(^2) 5
(^2) (^5) 105
3 3 5
3 7
10
Find the prime factorization. Use the divisibility rules
and a factor tree to help.
- 95 23. 114 24. 153 25. 390 26. 504
- 189 28. 225 29. 540 30. 1215 31. 2916
Solve for yto complete the prime factorization.
- 2 y 3 12 33. 2 y 82 34. 117 32 y
- 23 y 88 36. 110 y 5 11 37. 22 y 5 60
Make two different factor trees for each number.
Then write the prime factorization for each.
- 70 39. 99 40. 120 41. 40
- 48 43. 150 44. 84 45. 54
Composite.
Factor again.
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