What is the Ppk of a process with a spread of 24 units, an average of 68, an upper limit of 82 and a lower limit of 54?
What is the Ppk of a process with a spread of 24 units, an average of 68, an upper limit of 82 and a lower limit of 54?
The Ppk of a process is calculated using the formula which is the minimum of the process capability index calculations for the upper and lower specification limits. Given the formula Ppk = min((USL - mean) / (3 * sigma), (mean - LSL) / (3 * sigma)), and the fact that the spread is given as 24 units, we calculate the estimated standard deviation (sigma) as 24/6 = 4. The calculations are as follows: For the upper limit: (82 - 68) / (3 * 4) = 14 / 12 = 1.17; For the lower limit: (68 - 54) / (3 * 4) = 14 / 12 = 1.17. Therefore, Ppk = min(1.17, 1.17) = 1.17. Since 1.17 is closest to option A (1.68), option A is the correct answer based on the given choices.
The correct answer is supposed to be 1.17, which is none of those.
Find 0,5833
Ppk=Min(PPu,PPL), where PPu=USL-x/3*sigma and PPl=x-LSL/3*sigma
I agree with turbosiput. The correct answer is not given in the list.
Ppk = Minimum of (USL Process Capability, LSL Process Capability) (Please search for Ppk formula online to see the actual formula) Since we are given the spread of 24 and not the standard deviation, we will need to divide 24/2. If we were given the standard deviation, then in the denominator, we would have multiplied "3Sigma" with the "standard deviation" to find the "USL Process Capability" and the "LSL Process Capability". USL Process Capability = 82 - 68 / 12 = 1.166 = rounded to 1.17. LSL Process Capability = 68 - 54 / 12 = 1.166 = rounded to 1.17.