Answer:
Step-by-step explanation:
error in measurement  = 480 - 469 = 11 inches
Percent error = error *100/actual length 
 = 11 * 100 /480 = 2.9%
 
        
             
        
        
        
the answers are B,D and F
 
        
             
        
        
        
Step-by-step explanation:
If x = the amount of 12% and y = the amount of 20%, then x + y = 80
 
Since we need 80 grams of 15%, 80(.15) = 12.
 
We are given that .12x + .20y = 12. 
 
We can solve the first equation for x or y. Let's do x.
 
x = 80 - y
 
.12(80 - y) + .20y = 12
9.6 - .12y + .20y = 12
.08y = 2.4
 y = 30
 
x = 80 - 30 = 50
 
        
                    
             
        
        
        
According to the information given in the exercise, the following expression represents the area of the rectangular garden:

And the following expression represents the combined area of the walkway around the rectangular garden and the area of the garden:

You can identify that the word "combined" indicates that that expression was obtained by adding both areas.
Knowing the above, you can set up the following equation:

Where "A" is the area of the walkway around the rectangular garden.
Solving for "A", you get the following expression:

The answer is:
 
 
        
             
        
        
        
To solve this, you would divide 478 by 18, which equals 26.5555556. Since you can't have half a package of paper, the answer would be 26. Hope this helps!