Berserk Toy Figures is a toy company producing its copyrighted Guts figures.
The manufacturing process owned by the company creates the head part of the figure that is designed to be 19 mm wide with a standard deviation of 1.5 mm.
Head part of the figure is an important feature of the figure and regularly goes through the Quality Control. QC sample size is 35 parts. A recent batch of head parts appeared to have an average width of 18mm.
1.What is the probability of getting an average width equal to or less than 18mm?
2. Is there a quality problem? Use your finding in 1.
3. Berserk Toys is a boutique toy maker that could not afford to stop production and run a root cause analysis. How can the company tackle this problem and increase the confidence?