You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Q: Question: The bankerâ€™s discount on Rs. 1600 at 10% per annum is the same as true discount on Rs. 1680 for the same time and at the same rate. The time is :

 Option A: 2 months

 Option B: 4 months

 Option C: 6 months

 Option D: 7 months

 Option E: None

A: Option C
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Q: Question: Sum of 19 odd numbers is?

 Option A: 341

 Option B: 351

 Option C: 361

 Option D: 371

 Option E: 381

A: Option C
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Q: Question: A dealer offers a cash discount of 10% and still makes a profit of 35% when he further allows 20 articles to be sold at the cost price of 15 articles to a particular sticky bargainer. How much percent above the cost price were his articles listed?

 Option A: 80%

 Option B: 100%

 Option C: 120%

 Option D: 60%

 Option E: 90%

A:
Option B
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