Statistical Quality Control Techniques CTEL-TM-OTM Practice Questions (Page 2)

Questions 6–10

1. 6foundation · easy

   Which type of control chart would be most appropriate for monitoring the proportion of failed test cases per test cycle?

   • Ac-chart
   • BX-bar chart
   • Cp-chart
   • DR-chart
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2. 7application · medium

   A test manager analyzes the relationship between test effort (person-hours) and the number of defects found across 25 projects. The correlation coefficient is 0.95, and the regression equation is: Defects = 2 + 0.5 × (Test Effort). If a new project is planned with 100 person-hours of test effort, what is the predicted number of defects?

   • A50 defects
   • B102 defects
   • C52 defects
   • D95 defects
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4. 8application · medium

   A test manager introduced a new test automation framework and wants to determine if it significantly reduced the average test execution time compared to the previous manual approach. Historical data shows the manual approach averaged 45 minutes per test case. After running 30 automated test cases, the average was 40 minutes with a standard deviation of 8 minutes. What is the most appropriate next step?

   • APerform a one-sample t-test to determine if the mean execution time is significantly less than 45 minutes.
   • BConclude the automation is faster because 40 minutes is less than 45 minutes.
   • CUse a chi-square test to compare the variance of execution times.
   • DPerform a two-sample t-test comparing the manual and automated execution times.
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5. 9expert · hard

   A test manager wants to determine if a new test tool reduces the average number of defects escaping to production. Historical data shows an average of 5 escaped defects per release. After using the new tool for 20 releases, the average is 4.2 with a standard deviation of 1.5. The manager performs a one-sample t-test and obtains a p-value of 0.03. What is the most appropriate conclusion?

   • AThe new tool significantly reduces escaped defects because the p-value is less than 0.05.
   • BThe result is inconclusive because the sample size is too small.
   • CThe new tool does not significantly reduce escaped defects because the p-value is greater than 0.01.
   • DThe new tool reduces escaped defects by 0.8 defects per release.
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6. 10foundation · easy

   In hypothesis testing, what does the null hypothesis (H0) typically represent?

   • AThe alternative hypothesis that there is a significant effect
   • BThe hypothesis that the sample data are normally distributed
   • CThe hypothesis that the test process is stable
   • DThe assumption that there is no effect or no difference
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