CSSGB Six Sigma Green Belt Exam Questions & Answers 2026 (11–20)

Question 1

Examine the following customer service process. Which step is considered a value-added activity in a Lean analysis?

TheoryPractice · Accepted Answer

Staff assists customer with product selection. Lean analysis focuses on identifying steps in a process that enhance value from the customer's perspective. "Staff assists customer with product selection" is a value-added activity because it directly contributes to the service provided to the customer.

Question 2

In the context of retail management, determining the relationship between product prices and sales volume is essential. Based on the data provided in the table, which term best describes this kind of analysis? Product ID Price ($) Sales Volume P001 15 120 P002 20 180 P003 25 155 P004 30 130 P005 35 90

TheoryPractice · Accepted Answer

Correlation. The correct answer is Correlation. Correlation involves evaluating the degree to which one variable moves in relation to another. In this context, it refers to analyzing how changes in product prices (independent variable) affect sales volume (dependent variable). Congruency refers to similarity rather than a relationship. Coefficient is a component in correlation but not the term describing the analysis itself. Collateral is unrelated to this form of analysis.

Question 3

In assessing the impact of a Six Sigma intervention in a manufacturing process using regression analysis, which of the following steps is necessary when setting up your analysis? Intervention Stage Defect Rate Before (%) Defect Rate After (%) Initial 10 8 Middle 9 7 Final 8 6

TheoryPractice · Accepted Answer

Set the conditions for the test. In regression analysis, setting the conditions for the test is crucial to defining the assumptions and scope of the analysis. This includes deciding on null and alternative hypotheses, choosing a significance level, and understanding the regression model's assumptions. Calculating individual standard deviations or determining the hypothesis value directly is not part of setting up the conditions. Also, rejecting the null hypothesis is the correct action when the test statistic is beyond the critical values.

Question 4

In a manufacturing process, identifying the root causes of defects involves analyzing the flow of materials and information. Each defect is a result of a preceding issue, as there is no single absolute cause for defects. What is this principle called?

TheoryPractice · Accepted Answer

Causal chain. Answer: Causal chain A causal chain implies that each defect is the result of a prior issue, as there is no single absolute cause for defects. By determining correlation and causation, identification of all issues in the causal chain can be explored to improve quality. Process mapping is incorrect as it depicts the detailed steps involved in a process but does not inherently identify causal relationships. The cause-and-effect diagram is incorrect because it is a tool used to visualize potential causes of an issue, not the principle of causality. Root cause analysis is a problem-solving method but is not a description of the principle where causes precede effects.

Question 5

Consider the following data comparing two population proportions. Use a significance level of 0.05 to determine the rejection region for a right-tailed hypothesis test of the difference in population proportions. Population Sample Proportion ($$\hat{p}$$) Sample Size (n) Number of Successes (x) Population 1 0.4 100 40 Population 2 0.3 100 30

TheoryPractice · Accepted Answer

α to its right. Answer: α to its right In a right-tailed hypothesis test, the rejection region is determined by the area of α to the right side of the Z-distribution. This region represents the critical values where if the calculated statistic falls, the null hypothesis is rejected. The other options incorrectly identify regions that are not applicable to a right-tailed test. For instance, α/2 to its right is used in two-tailed tests.

Question 6

In a manufacturing plant, a new expedited process is introduced to reduce the defect rate in a product line. Consider the following scenarios and determine which one represents a Type II error. Scenario Hypothesis Reality Expedited Process Reduction in defect rate No actual reduction in defect rate Standard Process No change in defect rate True reduction in defect rate

TheoryPractice · Accepted Answer

Standard Process: No change in defect rate (H - True reduction in defect rate). A Type II error occurs when there is a failure to reject a false null hypothesis. In this context, the true state is a reduction in defect rate under the standard process (null: no change). However, the null hypothesis of 'no change' is not rejected, indicating the defect rate has not reduced.

Question 7

A company has implemented a new marketing strategy and wishes to analyze its impact on sales volume. Based on financial performance data analysis, what should the null hypothesis represent in this context?

TheoryPractice · Accepted Answer

Sales volume has not changed.. Answer: Sales volume has not changed. The null hypothesis (H₀) typically represents the idea that there is no impact or effect—in this case, it denotes that the new marketing strategy has not resulted in a change in sales volume. The alternative hypothesis (H₁) would suggest a change has occurred.

Question 8

A finance startup conducted a survey among their customers to measure satisfaction with their service. They found that 68% of the 800 respondents are satisfied. Calculate the 95% confidence interval for the true proportion of satisfied customers. Use $$Z_{\alpha/2} = 1.96$$ for your calculations.

TheoryPractice · Accepted Answer

68% +/- 3.2%. To calculate the confidence interval, we use the formula:  $$p \pm Z_{\alpha/2} \sqrt{\frac{p(1-p)}{n}}$$ Where $$p$$ = 0.68, $$n$$ = 800, and $$Z_{\alpha/2}$$ = 1.96. Confidence interval = $$0.68 \pm 1.96 \sqrt{\frac{0.68(1-0.68)}{800}}$$ Solving gives a confidence interval of approximately 68% +/- 3.2%.

Question 9

In a manufacturing process, an average of 10% of products are defective. If 50 items are produced in a batch, what is the variance in the number of defective items? Production Batch Defect Rate Batch Size 50 Defect Probability $$0.10$$

TheoryPractice · Accepted Answer

4.5. To find the variance of a binomial distribution, use the formula $$np(1 - p)$$ where $$n$$ is the number of trials (batch size) and $$p$$ is the probability of success (defect rate). Here, $$n = 50$$ and $$p = 0.10$$. Variance = $$50 	imes 0.10 	imes (1 - 0.10) = 4.5$$.

Question 10

In a manufacturing setting, a process has been improved by implementing Six Sigma methodologies. Which of the following values best represents the expected long-term shift in the process mean? Process Improvement Scenario Expected Mean Shift Application of Six Sigma 1.5 \sigma

TheoryPractice · Accepted Answer

1.5 σ. The correct answer is 1.5 σ. Implementing Six Sigma results in a long-term process mean shift of 1.5 σ, which accounts for variations over time. 3 σ and 5 σ are incorrect; they overestimate the shift in the mean. 'No shift' is incorrect as the typical process still experiences variation over time.

CSSGB Six Sigma Green Belt Exam Questions & Answers 2026 (11–20)

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