QUESTION $9$

A manufacturer embarking on a Six Sigma program sets the goal of having true Six Sigma capability for all processes by the end of the month. If their current process capabilit less than $2\mathrm{.}0$ and the process capability ratio is $1\mathrm{.}5,$ what must happen with the process standard deviation?

The process standard deviation must be reduced by $25\%.$

The process standard deviation must be reduced by $67\%.$

The process standard deviation must be reduced by $50\%.$

The process standard deviation must be reduced by $339\%.$