Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

Q: Problem: a merchant marks his goods up by 30 % and then offers a discount of 10 % on the marked price. what % profit does the merchant make after the discount ?
Options: a. 17 %, b. 25 %, c. 69 %, d. 31 %, e. 19 %

A: a
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Q: Problem: the average weight of 6 person ' s increases by 4.5 kg when a new person comes in place of one of them weighing 75 kg. what might be the weight of the new person ?
Options: a. 160 kg, b. 175 kg, c. 180 kg, d. 102 kg, e. 190 kg

A: d
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Q: Problem: the odds in favour of an events are 3: 5. the probability of occurrence of the event is
Options: a. 3 / 8, b. 2 / 7, c. 1 / 3, d. 2 / 5, e. 6 / 7

A:
a
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