The volume of a rectangular prism is L * W * H.
We are looking for whole numbers that multiply to 28.
There are 10 possible molds.
L,  W,  H
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28, 1, 1
1, 1, 28
14, 2, 1
1, 14, 2
1, 2, 14
7, 4, 1
4, 1, 7
7, 1, 4
7, 2, 2
2, 2, 7
        
             
        
        
        
Answer -15 because it would be 15 but the negative would be turned into a negative again 
 
        
             
        
        
        
Step-by-step explanation:
43 Is the solution after adding