A class of 16 boys averages 50.25 kg, and the remaining 8 boys average 45.15 kg. Determine the average weight of all boys.
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Answer: C. 48.55 kg
Explanation
Multiplying sixteen boys by their average weight yields a total mass of eight hundred four kilograms. Multiplying eight boys by their average weight yields a total mass of three hundred sixty one point two kilograms. Dividing the combined total mass by twenty four total students produces the final average weight. Weighted averages account for subgroups of different sizes within a larger population dataset. Total weight of a combined group equals the sum of all individual subgroup total weights. Dividing cumulative weight by total participant count determines the overall population mean.
Health researchers calculate demographic weight averages to monitor nutritional health trends across populations. School administrators use group averages to track physical development milestones among students. Quality control engineers apply weighted averages when combining batches of manufactured materials. Option A suggests forty seven point fifty five kilograms which underestimates the combined group mass. Option B suggests forty eight kilograms which ignores fractional components in subgroup totals. Option C suggests forty eight point fifty five kilograms which correctly reflects the weighted calculation.
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- Mathematics
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