The common factor would be 3 because 3 is the highest multiple of 15 and 9
        
                    
             
        
        
        
Answer:
28/55
Step-by-step explanation:
total no of beads are 11
red beads are 7
and white beads are 4
no of ways to take 2 beads from 11 beads are 11c2
that is( 11*10)/2=55
no of ways to take 1 red bead from 7 is 7c1 that is 7
no of ways to take 1 white bead from 4 is 4c1 is that is 4
required probability is( 7*4)/55=28/55
this question has already been answered on someone else's account so know this answer is 100% correct 
hope that helped :)
 
        
             
        
        
        
The answer is B 
step by step explanation:
        
                    
             
        
        
        
Assuming we have parallel lines, we can solve for x.
Since a = 3x - 10 (vertically opposite angles are equal),
3x - 10 = 2x + 15 (alternate angles are equal)
x = 25
Hence, angle a = 3(25) - 10 = 65°