Difficulty: Easy
Correct Answer: 16.25%
Explanation:
Introduction / Context:This question tests aggregation of pass/fail percentages across groups of different sizes. Compute the total passes, subtract from total candidates, and express the failures as a percentage of the total.
Given Data / Assumptions:Appeared: boys = 950, girls = 250. Pass rates: 90% of boys, 60% of girls.
Concept / Approach:Calculate passes separately by group, sum to get total passes, subtract from total candidates to get failures, and finally convert to a percentage of total appeared.
Step-by-Step Solution:
Boys passed = 0.90 * 950 = 855 Girls passed = 0.60 * 250 = 150 Total passed = 855 + 150 = 1005 Total candidates = 950 + 250 = 1200 Failed = 1200 − 1005 = 195 Failure % = (195 / 1200) * 100 = 16.25%Verification / Alternative check:Passed % = 1005/1200 * 100 = 83.75%; hence failed % = 100 − 83.75 = 16.25%.
Why Other Options Are Wrong:16.50% and 16.75% are close distractors, but exact arithmetic yields 16.25%.
Common Pitfalls:Rounding early or using the average of 90% and 60% without accounting for different group sizes.
Final Answer:16.25%
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