Difficulty: Easy
Correct Answer: ₹ 78.75
Explanation:
Introduction / Context: This question contrasts true discount (TD) and banker’s discount (BD). Given present worth (P) and TD, we can compute BD using a standard identity.
Given Data / Assumptions:
Concept / Approach: Banker’s discount is SI on face value: BD = F * r * t. True discount is SI on present worth: TD = P * r * t. Using r*t = TD/P, we obtain: BD = TD + (TD^2)/P.
Step-by-Step Solution: Compute banker’s gain BG = BD − TD = (TD^2)/P = 75^2 / 1500 = 5625 / 1500 = 3.75. Hence BD = TD + BG = 75 + 3.75 = 78.75.
Verification / Alternative check: If r*t = TD/P = 75/1500 = 0.05, then BD = F * 0.05 = 1575 * 0.05 = 78.75, matching the result.
Why Other Options Are Wrong: 77.75 and 76.75 do not match the identity; 82.75 and 80.00 misapply the formula.
Common Pitfalls: Confusing BD with TD; forgetting BD − TD = (TD^2)/P; or using face value instead of present worth in the TD expression.
Final Answer: ₹ 78.75
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