Basic Statistical Tools Flashcards
7 cards from real Lean Six Sigma Green Belt Certification practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Basic Statistical Tools flashcards as text
A dataset has a mean of 50 and a standard deviation of 5. What is the coefficient of variation (CV)?
Answer: 10%
CV = (standard deviation / mean) × 100 = (5 / 50) × 100 = 10%.
In a normal distribution, approximately what percentage of data falls within two standard deviations of the mean?
Answer: 95%
The empirical rule states approximately 95% of data falls within ±2 standard deviations.
Which measure of central tendency is most resistant to extreme outliers?
Answer: Median
The median is resistant to outliers because it is based on rank order, not the actual values.
A process produces parts with diameters measured at 10.1, 10.3, 9.8, 10.5, and 10.3 mm. What is the range?
Answer: 0.7 mm
Range = maximum − minimum = 10.5 − 9.8 = 0.7 mm.
What type of data results from counting defects per unit?
Answer: Attribute data
Counting defects produces discrete attribute (count) data, not continuous variable data.
A scatter plot shows points closely clustered around a line sloping downward from left to right. This indicates:
Answer: A strong negative correlation
A downward slope with tightly clustered points indicates a strong negative correlation between the two variables.
Which chart is used to display the frequency distribution of continuous data?
Answer: Histogram
A histogram displays the distribution of continuous data by grouping values into bins and showing frequency.