
Answer: Option (b) is correct.
Explanation:
Given that,
Pillows are manufactured in 40-pillow batch sizes
Cutting time = 4 minutes per pillow
Assembly time = 8 minutes per pillow
Takes 10 minutes to move a batch of pillows from cutting to assembly.
Value added lead time = Cutting time  + Assembly time
                   = 4 + 8
                   = 12 minutes
Non-value added lead time = move time
                       = 10 minutes
Total lead time = Value added lead time + Non-value added lead time
             = 12  + 10
             = 22 minutes
value-added ratio = [tex]\frac{value\ added\ time}{total\ lead\ time}[/tex]
               =  [tex]\frac{12}{22}[/tex]
               = 0.5454
               = 54.5%