Q. A shopkeeper allows three types of successive discounts as (i) 35% and 5%, (ii) 30% and 10%, (iii) 25% and 15% Which discount is the best for a purchaser?
Answer: First
Notes: (i) Equivalent discount $latex = \left ( 35+5-\frac{35\times 5}{100} \right )\%&s=1$ $latex = 40-1.75 = 38.25%$ (ii) Equivalent discount $latex = \left ( 30+10-\frac{30\times 10}{100} \right )\%&s=1$ $latex = 40-3 = 37%$ (iii) Equivalent discount $latex = \left ( 25+15-\frac{25\times 15}{100} \right )\%&s=1$ $latex = 40-3.75 = 36.25%$ Now we can easily say that first discount is best. Hence option [A] is our answer.

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