In a class of 40 students, the mean weight of 25 boys is 50 kg and the mean weight of 15 girls is 42 kg. What is the mean weight of the whole class (in kg)?
Class 9Measures of Central TendencyStatistics and Probability
A42
B94
C47
D52
Step-by-Step Solution
Total weight = 25×50+15×42=1250+630=1880 kg. Mean = 401880=47 kg.
Answer: C) 47
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