Given a simple high-school level math question, you are required to solve it and provide the final answer. The final answer is always a single number. These questions can range from a variety of topics like simple arithmetic, solving equations, converting a quantity from one unit to another, finding remainders/GCD/LCM, finding probabilities etc. Each question has only one correct answer. This answer can be a positive or negative integer, a fraction or a decimal number. If the answer is a negative number use the hyphen (e.g. -42) symbol for the minus sign. For decimal numbers, do not add extra zeros after the decimal point. For fractional numbers, separate the numerator and denominator using a forward slash (e.g. 3/25).

Q: What is 51/2 of a millisecond in microseconds?

A: 25500
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Q: 15 + (7 + -17)/1

A: 5
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Q: What is prob of sequence xi when two letters picked without replacement from {b: 3, x: 5, q: 1, i: 6, n: 3}?

A:
5/51
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