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 prob of picking 1 u and 3 f when four letters picked without replacement from wfffsmfwu?

A: 2/63
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Q: Let c = 5 + 0. Solve -c*u = -2*u + 3 for u.

A: -1
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Q: Solve 0 = j - 2*r + 16 - 8, 0 = 2*j + 2*r + 4 for j.

A:
-4
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