It is put to use Six Sigma had 3.4 defects per million opportunities (DPMO) from the start, allowing for a 1.5-sigma process shift. However, the definition of zero faults is a little hazy. Perhaps the area beyond 3.4 DPMO is referred to by the term "zero faults.", that's why Before being released, large computer programs, such as operating systems, must have no faults the wrong choice.
The gear ratios would look like A:B=1:9 and C:D=1:32 if you are just needing the gear teeth ratio. Not a lot of information to go off of from the question though