Difficulty: Easy
Correct Answer: ₹360
Explanation:
Introduction / Context:A straightforward computation: increasing a known base price by a given percentage. This type of question is common in shopping, taxation (e.g., GST), and inflation computations, where the new amount must be calculated from the original value and a single rate of change.
Given Data / Assumptions:
Concept / Approach:For a single increase of r%, multiply the original value by (1 + r/100). Here r = 20, so factor = 1.20. This compact method avoids separate steps of calculating the increment first and then adding it back, though both methods yield the same result.
Step-by-Step Solution:
Increase amount = 20% of 300 = 0.20 * 300 = ₹60 Final price = 300 + 60 = ₹360 Equivalently, 300 * 1.20 = ₹360Verification / Alternative check:Reverse check: If final is 360, the increase over 300 is 60, and 60/300 * 100% = 20%. This confirms accuracy.
Why Other Options Are Wrong:₹350, ₹365, and ₹370 correspond to incorrect increase amounts (16.7%, 21.7%, 23.3% respectively). ₹340 implies only a 13.3% increase, not 20%.
Common Pitfalls:Mixing up the base for percentage increase or mistakenly applying further changes. Ensure the percentage is always applied to the stated original price unless clearly specified otherwise.
Final Answer:₹360
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