IASSC Certified Lean Six Sigma Black Belt (ICBB) — Question 66

Sally and Sara sell flower pots at their garage sale. Martha motivates Rose mentioning that they will sell a minimum of 16 pots per day if the outside temperature exceeds 60o F. From a sample, whose population is assumed to follow a Normal Distribution, taken for 30 days at 60 degrees or more an average of 15.2 pots per day were sold with a Standard Deviation of 0.6 pots. What is the Z value for this sales process?

Answer options

• A. 0.67
• B. 1.13
• C. 1.33
• D. 2.66

Correct answer: C

Explanation

The Z value is calculated using the formula Z = (X - μ) / σ, where X is the target value (16), μ is the mean (15.2), and σ is the standard deviation (0.6). Plugging in the numbers gives Z = (16 - 15.2) / 0.6 = 1.33. The other options do not reflect the correct calculation and therefore are incorrect.