Quality assurance and control charts (Edexcel GCSE Statistics): Quizzes
📚Quizzes
Practise the questions
10 questions from this quiz
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Practise the questions
10 questions from this quiz
What is the main purpose of control charts in quality control?
What is the main purpose of control charts in quality control?
To monitor production quality
What does the target mean (μ) represent on a control chart?
What does the target mean (μ) represent on a control chart?
Ideal average value
What are warning limits set at?
What are warning limits set at?
±2σ from target
Why take samples rather than testing every item?
Why take samples rather than testing every item?
To save time and costs
If a sample mean falls outside action limits, what is the next step?
If a sample mean falls outside action limits, what is the next step?
Take a second test
What percentage of sample means should fall within ±2σ in a working process?
What percentage of sample means should fall within ±2σ in a working process?
About 95%
What action is needed if a sample mean is within warning limits?
What action is needed if a sample mean is within warning limits?
No action needed
In quality control, what does a sample mean within ±3σ indicate?
In quality control, what does a sample mean within ±3σ indicate?
Process is normal
What is the probability that a sample mean falls outside action limits if the process is normal?
What is the probability that a sample mean falls outside action limits if the process is normal?
0.2%
How is the sample mean calculated?
How is the sample mean calculated?
Sum of values ÷ sample size