Meena Chavan Corp.\'s computer chip production process yields DRAM chips with an
ID: 394040 • Letter: M
Question
Meena Chavan Corp.'s computer chip production process yields DRAM chips with an average life of 1,600 hours and = 80 hours. The tolerance upper and lower specification limits are 2,200 hours and 1,500 hours, respectively. Based on the given information, the process capability ratio, Cp 1.46 (round your response to two decimal places) Based on the process capability ratio (Cp) for the given information, one can say that the process is very much capable of producing the chips to the design specifications For the given information, the process capability index (Cpk)(round your response to two decimal places)Explanation / Answer
Following are the relevant data for calculation of Cpk :
Upper specification Limit = USL = 2200 hour
Lower Specification Limit = LSL = 1500 hour
Process mean ( i.e. average life of DRAM chip ) = 1600 hours
Standard deviation of process = Sd = 80 hours
Therefore,
Process Capability Index , Cpk
= Minimum ( ( USL – m)/ 3xSd , ( m – LSL)/3xSd)
= Minimum ( ( 2200 – 1600)/3x80 , ( 1600 – 1500) / 3 x 80) )
= Minimum ( 600/240 . 100/240)
= Minimum ( 2.5, 0.4166)
= 0.4166 ( 0.42 rounded to 2 decimal places )
The process capability index ( Cpk) = 0.42
The process capability index ( Cpk) = 0.42