Answer:
40, 60, 80
Step-by-step explanation:
The sum of angles in all triangles is 180 degrees (assuming you are talking about Euclidean geometry). If 2:3:4 is the ratio then 
2x + 3x + 4x = 180
9x = 180
x = 20
Now that we now what x is, we can find the respective angles by plugging the value of x in. The angles are 40, 60, and 80 respectively.
 
        
                    
             
        
        
        
Answer:
12/15
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
8 months because 3 divided by 12 equals 4 times 2 equals 8
Step-by-step explanation:
 
        
                    
             
        
        
        
The answer is in the image 
 
        
             
        
        
        
First make the denominators of the fractions the same by multiplying.

 × 

=

Now we just need to add the fractions together

= 

9/6 would be the answer, but it can be simplified further, then converted into decimal form.

 ÷ 

=
 =1.5 yards
=1.5 yardsYour final answer is 1.5 yards of ribbon are needed.