On a bill due 4 months hence at 15% p.a., the banker's discount is ₹420. What is the true discount?
Aptitude
Banker's Discount
Difficulty: Easy
Choose an option
-
A₹400
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B₹420
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C₹380
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D₹405
Answer
Correct Answer: ₹400
Explanation
Given data
- Time t = 4 months = 1÷3 year; rate r = 15% p.a.
- BD = ₹420.
Concept/ApproachBD = S r t ⇒ find face value S, then TD = S r t ÷ (1 + r t).
Step-by-Step calculation BD = S × 0.15 × (1÷3) = S × 0.05 = 420 S = 420 ÷ 0.05 = ₹8400 TD = S × 0.05 ÷ (1 + 0.05) = 420 ÷ 1.05 = ₹400
Verification/AlternativeRelation BD ÷ TD = 1 + r t = 1.05 ⇒ TD = BD ÷ 1.05 = 420 ÷ 1.05 = ₹400.
Final Answer₹400