Difficulty: Medium
Correct Answer: One-eighth of the boys play neither cricket nor football.
Explanation:
Introduction / Context:This is a classic two-set (football and cricket) counting problem. We are given overall fractions for football and cricket participation and an additional constraint about a portion of cricket players not playing football. We must find the fraction who play neither game.
Given Data / Assumptions:
Concept / Approach:Use set identities: total = F-only + C-only + both + neither. Also, F = F-only + both, and C = C-only + both. Solve systematically.
Step-by-Step Solution:
Let total boys T = 1.Given C = 1/2. C-only = 1/8. Therefore, both = C − C-only = 1/2 − 1/8 = 3/8.Given F = 3/4. Since both = 3/8, F-only = F − both = 3/4 − 3/8 = 3/8.Sum known participants = F-only + C-only + both = 3/8 + 1/8 + 3/8 = 7/8.Neither = 1 − 7/8 = 1/8.Verification / Alternative check:Check totals: 3/8 (F-only) + 3/8 (both) = 3/4 = F, OK. 1/8 (C-only) + 3/8 (both) = 1/2 = C, OK. Complement gives 1/8 neither, consistent.
Why Other Options Are Wrong:
Common Pitfalls:Forgetting that “one-fourth of cricket players do not play football” applies to cricket subset only, or double-counting the intersection.
Final Answer:One-eighth of the boys play neither cricket nor football.
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