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 person crosses a 800 m long street in 5 minutes. what is his speed in km per hour ?
Options: a. 1.23, b. 2.86, c. 4.36, d. 9.25, e. 9.61

A: e
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Q: Problem: arjun started a business with rs. 20,000 and is joined afterwards by anoop with rs. 30, 000. after how many months did anoop join if the profits at the end of the year are divided equally ?
Options: a. 3, b. 4, c. 5, d. 6, e. 7

A: b
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Q: Problem: how many times digit 5 is used while writing numbers from 100 to 1000 ?
Options: a. 648, b. 300, c. 252, d. 225, e. 290

A:
e
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