Difficulty: Easy
Correct Answer: 90
Explanation:
Introduction / Context:
This is a neat arithmetic application of equal counts across denominations. The total value is a simple multiple of the sum of the denominations, scaled by the common count. We then multiply by three to get the total number of notes.
Given Data / Assumptions:
Concept / Approach:
Total value = n*(1 + 5 + 10) = 16n. Solve 16n = 480, then compute total notes = 3n. This linear setup avoids any need for trial and error.
Step-by-Step Solution:
Verification / Alternative check:
Compute value by denomination: 30*₹1 + 30*₹5 + 30*₹10 = ₹30 + ₹150 + ₹300 = ₹480, exactly the given total.
Why Other Options Are Wrong:
Common Pitfalls:
Confusing equal value with equal count, or summing denominations incorrectly (1 + 5 + 10 = 16, not 15).
Final Answer:
90
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