Question

A manager states that his process is really working well. Out of 1,500 parts, 1,477 were produced free of a particular defect and passed inspection. Based upon Six Sigma theory, how would you rate this performance, other things being equal?

Answer 1

The answer is explained below

Explanation:

STEP 1

Out of 1500 units produced by a company 1,477 are found to be free of a particular type of defect. One needs to rate the performance based on Six Sigma Theory.

STEP 2

Manager can define the performance of a product using defects per million units DPMO metric

DPMO can be find by using

DPMO = Total number of defects in a sample/ No. of opportunities of per error per unit x No. of units * 1,000,000

= 1500 - 1477/ 1 x 1500* 1,000,000

= 23/1500

= 15,333,33

The defect rate of the process can be find by

Defect rate = No. of defects/ No. of units * 100

= 1500 - 1477/1500 * 100

= 23/1500 * 100

= 1.53%

Six Sigma theory focuses on achieving 3.4 defects per million for a certain period of time. However in this, performance of the process is not as good as stated by the manager.

Answer 2

Given Information:

Total units = 1500

Defect free units = 1477

Required Information:

six-sigma performance = ?

Answer:

six-sigma performance:

DPU = 0.0153333

DMPU = 15333.33

Step-by-step explanation:

The six sigma is measure of quality enhancement in the organizations. There are six levels 1 to 6 where 1 represents lowest quality level and 6 represents highest quality level .

No. of defective units = total no. of units - defect free units

No. of defective units = 1500 - 1477

No. of defective units = 23

Defects per unit (DPU) is given by

DPU = No. of defective units/total no. of units

DPU = 23/1500

DPU = 0.0153333

DPU = 1.53 %

Defects per million units (DMPU) is given by

DMPU = DPU*1 million

DMPU = 0.0153333*1,000,000

DMPU = 15333.33

For six-sigma level DMPU must be equal or less than 3.4.

15333.33 is way more than 3.4 so the performance is not that great!