I have tried every possible way to mix numbers together and cannot figure out how to get the total idle time per cycle. I do the practice questions and can never seem to get the answer. I need help with the answer to e and also an explanation how to figure it out.

b) Given the demand, the cycle time for the production of the new train set =31.30 seconds (round your response to one decimal place). c) The theoretical minimum number of workstations =4 (round your response up to the next whole number). Were you able to assign all the tasks to the theoretical minimum number of workstations? e) The total idle time per cycle for the process = seconds (enter your response as a whole number)