This set of Statistical Quality Control Multiple Choice Questions & Answers (MCQs) focuses on “Process Capability Ratios – 1”.

1. Process capability ratio is expressed as ____

View Answer

2. USL in the formula of PCR is _____

a) Upper safe limit

b) Ultimate safe limit

c) Upper specification limit

d) Ultimate specification limit

View Answer

Explanation: USL in the formula of PCR or process capability ratio is the Upper Specification Limit. This denotes the maximum tolerable value for a quality characteristic.

3. The LSL in the C_{p} is called ____________

a) Lower safe limit

b) Largest safe limit

c) Largest specification limit

d) Lower specification limit

View Answer

Explanation: The LSL, in the formula of the Process Capability Ratio, C

_{p}is the Lower Specification Limit value of the quality characteristic. It specifies the lowest possible value for the quality characteristic for the process to be in statistical control.

4. When the process standard deviation σ is unknown for a process, to calculate the PCR we use ____

a) The mean

b) The variance

c) The sample average

d) The estimate of σ

View Answer

Explanation: It is common that the process standard deviation is not known for the process. In this case, to calculate the PCR, we use the estimate of the process standard deviation.

5. We use ____ to calculate the estimate of the process standard deviation.

a) Sample standard deviation

b) Sample average

c) Sample variance

d) Sample mean

View Answer

Explanation: When the process standard deviation is not known, we use the estimate of the process standard deviation. This estimate is calculated by using the sample standard deviation, s.

6. How is s (Sample standard deviation) calculated?

a) s = R/2

b) s = R/2d_{2}

c) s = R/d_{2}

d) s = 2R/d_{2}

View Answer

Explanation: The sample standard deviation, s, used for the estimation of the process standard deviation, is calculated by the formula:

s = R/d

_{2}.

7. The estimate of the C_{p} is calculated by _____

View Answer

8. If the estimate of the process standard deviation is 0.1368, and the USL for the quality characteristic is 2.00, and the LSL=2.00, what will be the value of the estimate of PCR C_{p} is ___

a) 1.21

b) 1.19

c) 1.13

d) 1.31

View Answer

9. The percentage of the specification band used by the process is calculated by formula ______

View Answer

Explanation: The percentages of the specification band used by any process is calculated by the following formula,

10. If the process capability ratio C_{p} is 1.532, what percentages of the specification band will be used by the process?

a) 65.27%

b) 75.11%

c) 44.21%

d) 21.42%

View Answer

Explanation: The percentages of specification band used by the process is calculated by,

When we put values, we get, P=65.27%.

11. The one sided process capability ratio that uses the USL of the quality characteristic, is written as ____

View Answer

Explanation: The one sided process capability ratio that uses the USL of the quality characteristic is written as,

12. For a process, the process standard deviation is 32. If the mean of the process is 364, and the upper specification limit is 400, what will be the one side process capability ratio which uses USL of the quality characteristic?

a) 1.242

b) 1.135

c) 1.125

d) 0.991

View Answer

13. What is the formula to calculate the one sided process capability which uses lower specification limit?

View Answer

Explanation: The formula to calculate the one sided process capability which uses lower specification limit of the quality characteristic,

14. Process capability ratio C_{p} cannot be zero.

a) True

b) False

View Answer

Explanation: Process capability ratio C

_{p}cannot be zero as the USL and LSL difference can’t be zero and the standard deviation of the process also can’t be infinite. So we can say that that C

_{p}can’t be zero.

15. Increase in process capability ratio C_{p} states that there is a increase in the percentage of the specification band used.

a) True

b) False

View Answer

Explanation: We know that,

So an increase in the PCR C

_{p}shows an decrease in the percentage of the specification band used.

**Sanfoundry Global Education & Learning Series – Statistical Quality Control.**

To practice all areas of Statistical Quality Control, __here is complete set of 1000+ Multiple Choice Questions and Answers__.