Q. If a shirt costs 64 Rs. After 20% is allowed, what was its original price?
Answer: 80 Rs.
Notes: If the original cost of shirt be x, then $latex x\times \frac{80}{100} = 64&s=1$ $latex => x = \frac{64\times 100}{80} = 80 Rs.&s=1$ Hence option [B] is the right answer.

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