Conclude That the Finished Milled Size of the Components Are Normally Distributed

PROBLEM xxxxx is a large engineering company, manufacturing steel products for the building industry. As the company has grown over the last few years, the products produced have not only increased in volume but the high quality standard and minimal tolerance to which they are manufactured has become more of a customer requirement and therefore an important company objective.
One particular high sales volume product, is assembled using numerous steel bracket components which themselves are milled to size on a CNC lath. …