Question

Difficulty: MediumDescriptive Statistics Interpretation

The table below details operational metrics for 10 wind turbines managed by a renewable energy utility during the previous calendar year:

Turbine IDRegionCapacity (MW)Availability (%)Unplanned Maintenance (hours)
T-01Offshore6.094.248
T-02Onshore4.097.518
T-03Offshore8.091.084
T-04Onshore3.598.112
T-05Offshore6.095.836
T-06Offshore8.093.562
T-07Onshore4.096.024
T-08Offshore6.092.470
T-09Onshore3.598.88
T-10Offshore8.096.528

Based on the table, what is the median number of unplanned maintenance hours for turbines located in the Offshore region?

Answer: 55 hours

Answer

The median number of unplanned maintenance hours for turbines in the Offshore region is 55 hours.
Filtering the table for Offshore turbines yields 6 entries with unplanned maintenance hours of 48, 84, 36, 62, 70, and 28. Arranging these values in ascending order gives {28, 36, 48, 62, 70, 84}. Because the count is even (N = 6), the median is the average of the 3rd and 4th elements: (48 + 62) / 2 = 55 hours.

Step-by-Step Solution

1
Filter the dataset by Region
Identified 6 turbines in the Offshore region: T-01 (48 hrs), T-03 (84 hrs), T-05 (36 hrs), T-06 (62 hrs), T-08 (70 hrs), and T-10 (28 hrs).
The question specifically restricts the calculation to turbines operating in the Offshore region.
2
Sort the filtered unplanned maintenance hours in ascending order
Ordered set: 28, 36, 48, 62, 70, 84.
Finding the median requires data elements to be arranged sequentially.
3
Calculate the median of the even-count dataset (N = 6)
The two middle values are the 3rd element (48) and the 4th element (62). Mean = (48 + 62) / 2 = 55.
When a dataset contains an even number of observations, the median is the arithmetic average of the two central terms.

Key Concept

Descriptive Statistics Interpretation (Median of Even-Count Filtered Subsets)
Estimated Time:1m 30s
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