<span>Only if " 20% " is the same as " 10% of 10% " . What do you think ?</span>
        
             
        
        
        
$3.75/6 ounces
= 0.625 unit price
        
             
        
        
        
$50 each.................... hope it helped
        
             
        
        
        
Answer:
Step-by-step explanation:
Volume of the box  =  x³ +11x² + 20x – 32        I think the ' is a typo for ³
       the width is x-1    and the height is x+8       
 Find an expression for the length
        Vol = LWH    solve L
         Vol / (WH)   =  L     so
L  =  (x³ +11x² + 20x – 32) / (x-1) (x+8)      
                     so it would help to factor the numerator
        (x³ +11x² + 20x – 32)       I'm willing to bet (x-1) and  (x+8) are factors
                                                but I will plot the equation to find the three roots
         (x³ +11x² + 20x – 32)  = (x-1) (x+8) (x+4)
L  =  (x³ +11x² + 20x – 32) / (x-1) (x+8) 
    =  (x-1) (x+8) (x+4) / (x-1) (x+8)           the (x-1) and (x+8) cancel out leaving
L =   (x + 4)