

1. 
Based on the factor trees, what is the greatest common factor of 8 and 20? 


A. 
4 
B. 
8 


C. 
2 
D. 
20 


Hint 


2. 
What is the greatest common factor of 25a^{2}b and 5ab^{2}? 


A. 
5a^{2}b^{2} 
B. 
5ab 


C. 
5 
D. 
5ab^{2} 


Hint 


3. 
What is the greatest common factor of 16x^{2} and 12x? 


A. 
16x^{2} 
B. 
12x 


C. 
4x^{2} 
D. 
4x 


Hint 


4. 
What is the greatest common factor of 64 and 40? 


A. 
20 
B. 
2 


C. 
4 
D. 
8 


Hint 


5. 
What is the greatest common factor of 39 and 18? 


A. 
9 
B. 
6 


C. 
13 
D. 
3 


Hint 


