Data Management (QUIZ)

• A company wants to summarize employee performance ratings for annual reports. Which branch of statistics should they use?

  
  

  
  

  Answer: C. Descriptive Statistics
• A researcher wants to predict future customer trends based on past data. Whixh type of statistics would be most appropriate?

  Answer:

  
  

  A. Inferential Statistics
• What term describes assigning numerical values to obervations according to specific rules?

  
  

  Answer: B. Measurement
• A project manager ranks the priority of engineering tasks as "1st: Equipment Installation," "2nd; Safety Inspection," and "3rd Performance Testing." What scale of measurement is being used for this prioritization?

  
  

  
  

  Answer: Ordinal Scale
• An industrial engineer categorizes the types of materials used in a manufacturing process into groups such "Metal," "Plastic," "Ceramic," and "Composite." What scale of measurement is being used for this categorization?

  
  

  Answer: Nominal Scale
• What type of statistical tools provide information about averages, rankings, or categories for large data sets?

  
  

  Answer: Measures of Central Tendency
• A civil engineer measures the thickness of a concrete slab at five different points on a construction site: 15cm, 18cm, 16cm, 20cm, and 17cm. What is the average thickness of the slab?

  
  

  Answer: 17.2cm
• Which term refers to the midpoint of a data distribution, dividing it into two equal halves?

  
  

  Answer: B. Median
• A manufacturing plant records the number of hours taken to complete a series of maintenance tasks on different machines. The hours are as follows: 7,5, 8, 6, 9, 7, 6, 8, 7, 6. What is the median time to complete a maintenance task?

  Answer: B. 7
• What is the most frequently occuring value in a data set?

  Answer: C. Mode
• Which three measures provide information about the spread or central location of a distribution?

  
  

  Answer: Range, Standard Deviation, and Variance
• The times (in hours) taken by six machines to complete a specific task are 8.5, 9.0, 7.0, 6.5, 8.0, and 7.5. What is the range of the times taken to complete the task?

  
  

  Answer: D. 2.50
• The efficiency ratings of eight machines (measured in percentage) are: 85%, 90%, 88%, 92%, 89%, 91%, 84%, and 87%. What is the mean efficiency rating (rounded to the nearest hundredth)?

  
  

  Answer: 88.25%
• A factory tracks the number of defective products produced each day over a week. The numbers are 8, 12, 15, 10, 8, 9, and 8. What is the mode of defective products?

  
  

  Answer: A.8
• A chemical engineer measures the reaction times (in hours) for a series of experiments conducted on a new catalyst. The recorded times are: 1.2, 1.4, 1.5, 1.7, and 1.8 hours. What is the median reaction time?

  Answer: 1.5 hours
• When comparing groups with different means and standard deviation, a common scale is used to make scores comparable. What is this scale called?

  
  

  Answer: Z-score
• If Maria scores in the 75th percentile on a Math Placement Test, what does indicate?

  Answer: 75% of test-takers scored lower than Maria.
• What term refers to dividing a distribution into four equal parts?

  Answer: B. Quartile
• The third quartile (Q3) corresponds to which percentile Rank?

  Answer: C. 75th Percentile
• In a box-and-whisker plot, what does the middle point or dot typically represent?

  Answer: B. Median
• Which type of curve represents a unimodal frequency distribution with scores symetrically distributed around the mean?

  Answer: C. Normal Curve
• Which table shows percentages for one side of a symmetric curve, with body sides yielding equal percentages?

  Answer: A. Z-Table
• A metallurgical engineer measures the tensile strength of a batch of steel samples. The average tensile strength is 500MPa with a standard deviation of 25MPa. What is the z-score for a steel sample with a tensile strength of 460 MPa?

  Answer: A. -1.60
• A construction company tested the strength of a batch of concrete cylinders under pressure. The Strength values in megapascals (MPa) were 30, 32, 28, 50, 25, 29, 30, 30. What is the standard deviation of the strength values.

  Answer: C.7.15 MPa
• A ceramics engineer is testing the compressive strength of ceramic samples. The mean compressive strength of the samples is 250 MPa with a standard deviation of 10 MPa. What is the z-score for a sample that has a compressive strength of 240 MPa?

  Answer: A. -1.00
• A chemical plant produces batches of a particular chemical compound with a target concentration of 5% the concentration is normally distributed with a mean of 5% and a standard deviation of 0.2%. What percentage of batches will have a concentration less than 4.8%?

  Answer: A. 15.87%
• In a semiconductor fabrication plant, the thickness of a wafer is normally distributed with a mean of 0.5 mm and a standard deviation of 0.02 mm. What is the probability that a randomly selected wafer will have a thickness between 0.48 mm and 0.52?

  Answer: 0.6827
• In a manufacturing process, the weight of metal parts is normally distributed with a mean of 100 grams and a standard deviation of 3 grams. What percentage of metal parts will weigh more that 105 grams?

  Answer: 4.75%
• In a heat treatment process for metal parts, the average temperatures is 200C with a standard deviation of 5C. What is the Z-score for an aluminum bar that measures 210C?

  Answer: A. 2
• A software engineer analyzes the performance times of two algorithms. The first algorithm took 2.5 seconds, with a mean execution time of 2 seconds and a standard deviation of 0.3 seconds. The second algorithm took 3 seconds, with a mean execution time of 2.5 seconds and a standard deviation of 0.4 seconds. Which algorithm performed better relative to other algorithms?

  Answer: B. Second Algorithm
• In a manufacturing process for steel bars, the mean weight is 1.2 kg with a standard deviation of 0.05kg. A particular bar has a z-score of 0.8. What is the weight of this steel bar?

  Answer: 1.24kg
• Which statistical tool measures the strength of association between two variables but cannot determine causality?

  Answer: C. Pearson R Correlation
• If the value of r is _____, it indicates no linear correlation between two variables.

  
  

  Answer: 0
• A substantial linear relationship exists when the value of r falls within which range?

  
  

  Answer Between 0.40 and 0.70
• If the Pearson correlation coefficient r is calculated to be 0.99, what does it suggest about the relationship?

  
  

  Answer: A. Very Dependable relationship
• Which statistical method is used to make predictions about one variable based on another?

  Answer: Linear Regression
• What type of graph uses of dots to represent values of two variables and is essential for determining the regression line?

  Answer: A. Scatter plot
• An electrical engineer wants to examine the relationship between voltage and current in a circuit. Which tool would best help in analyzing how changes in voltage affect current?

  
  

  Answer: Linear regression
• A civil engineering team is studying the effect of different soil types on the strength of concrete. What would be the best way to visually represent the relationship between the soil type and concrete strength?

  
  

  Answer: D. Scatter plot
• A production manager in a factory wants to analyze how machine speed influences the number of defects in a batch. What statistical tool would be best to determine the strength of the relationship between speed and defects?

  
  

  Answer: Pearson Correlation