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: Three letters picked without replacement from {j: 2, y: 2, k: 1, u: 4}. Give prob of picking 2 j and 1 u.

A: 1/21
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Q: Solve -4*f = 3*o - 3 + 4, 2*o - 3*f - 5 = 0 for o.

A: 1
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Q: Suppose 0 = -3*a + 3*r + 201, -4*a + 4*r + 196 = -a. Calculate the highest common factor of 8 and a.

A:
8
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