Difficulty: Easy
Correct Answer: 520
Explanation:
Introduction / Context:
This aptitude question tests percentage application in exams. The key idea is that the qualifying cutoff is a fixed percentage of the maximum marks. If a candidate falls short by a given amount, we can back-calculate the maximum possible marks of the test paper using simple algebra with percentages.
Given Data / Assumptions:
Concept / Approach:
The qualifying cutoff = 40% of M = 0.40 * M. “Failed by 8 marks” means the candidate’s score is 8 less than the cutoff. So candidate score + 8 = cutoff. From that, solve for M directly.
Step-by-Step Solution:
Let M be the maximum marks.Cutoff to qualify = 40% of M = 0.40 * M.Given: 200 is 8 less than the cutoff ⇒ 200 + 8 = 0.40 * M.Compute: 208 = 0.40 * M.Therefore M = 208 / 0.40 = 520.
Verification / Alternative check:
40% of 520 is 0.40 * 520 = 208. The candidate has 200, which is exactly 8 less than 208 as stated. This confirms the calculation is consistent.
Why Other Options Are Wrong:
540: 40% is 216, not 208; the shortfall would be 16, not 8.502: 40% is 200.8; shortfall would be 0.8, not 8.Couldn’t be determined: Sufficient data exists to find M uniquely.
Common Pitfalls:
Confusing “failed by 8” as “scored 8” or using 60% instead of 40%. Another error is subtracting 8 from the cutoff incorrectly or using 8% instead of 8 marks. Keep units straight: marks vs percentages.
Final Answer:
520
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