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: Solve 96*r - 13 = 91*r + 2*u, 3*u - 12 = -3*r for r.

A: 3
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Q: What comes next: -27, -49, -73, -99?

A: -127
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Q: What is prob of picking 2 i and 1 a when three letters picked without replacement from {u: 2, a: 1, i: 14}?

A:
91/680
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