Part 1
I would determine the productivity of the kitchen staff and wait staff by breaking down the output of each person in each section. Since we know how many meals are served each day, we just have to break them down into who did what to figure out how productive each section really is.
If I wanted to improve productivity of the kitchen staff, the one area that I would look at changing and/or improving would be quality management. I think that it would be paramount to decide how quality could be measured besides the rating scale and to let everyone know that they are involved in the measurement of the quality of the section as a whole. Brand recognition will only take you so far, we need to make sure that we have the right people for the job and to ensure that are customers are going to have an enjoyable experience and visit our restaurants again in the future.
Part 2 To find the answer to this equation, I first found the current rate of diagnose/fix in order to find his current daily productivity. To do this I did the following;
8hr day = 2hours = 4 prob. per day 2hrx1problem 1 problem
With the new system his rate would be as follows;
8hr day = 1hour - 1 hr daily maintenance = 7 prob. day 1 hr x1problem 1 problem
*At this new rate, the productivity would be increased by %75 with this new