Gosh, I've done this problem before. Let's start with 13. In this problem, we're basically just skip counting. For example, in the roses row, in the second bouquet, we know we have to add 4 more flowers, so we can document 8. Continue to skip count for both. For 15, we would have about 96 more movie posters remaining, making our ratio 96:x. So, 96:x = 120:100. Therefore, x would equal 80- as 96:80 equals 120:100. If she needs 80 and already had 100, she should sell 20 posters. Hope this helped.
        
             
        
        
        
Some symbols are missing. I'm assuming you meant to put in a horseshoe symbol like so 

If so, then the contrapositive of that would be 

 which is the final answer. 
The tilde sign 

 means "not" so writing 

 means "not q" which is the complete opposite of q. 
 
        
             
        
        
        
no thanks but I'll see if I can get friends to join
 
        
                    
             
        
        
        
Answer:
4
Step-by-step explanation:
Given that:
Let the two numbers = a and b
H. C. F of the two numbers = 2
L.C.M of the two numbers = 54
If a = 27 ; b =? 
The product of a and b = product of their L. C. M and H. C. F ;
HENCE ;
27 * b = 2 * 54
27b = 108
b = 108/27
b = 4
Hence, second number is 4
 
        
             
        
        
        

just a plain vanilla substitution