hard · GMAT Quant
A logistics analyst calculated the delivery duration variance for two dispatch hubs. Hub X processed 8 shipments with a sample variance of 21 square hours (calculated using n - 1). Hub Y processed 12 shipments with a population variance of 25 square hours (calculated using n). If both hubs maintained the identical average delivery duration of 14 hours
What is the unbiased sample variance, in square hours, for the combined pool of 20 shipments?
- dfrac46819
- dfrac44720
- dfrac44719
- dfrac42219
- dfrac1175
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