Difficulty: Medium
Correct Answer: 72.42 inches
Explanation:
Introduction / Context:
When combining groups with different averages and sizes, use weighted averages: convert all measures to a common unit, multiply each group’s average by its headcount, add, then divide by the total headcount.
Given Data / Assumptions:
Concept / Approach:
Overall average = (sum of all individual heights) / (total players). Equivalently, (average_A * count_A + average_B * count_B) / (count_A + count_B).
Step-by-Step Solution:
Verification / Alternative check:
The result must lie between 71 and 74 and lean toward 71–74 weighted by 20 vs 18; 72.42 is consistent and closer to 71 because A has slightly more players.
Why Other Options Are Wrong:
Common Pitfalls:
Using an unweighted mean of 71 and 74 (which would be 72.5) or mixing feet and inches without converting.
Final Answer:
72.42 inches
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