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: Two letters picked without replacement from vvdv. Give prob of sequence vv.

A: 1/2
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Q: Suppose 2*y + 12 = 6*y. Suppose y = f - 15. Solve -8 = -4*w, -3*d - 4*w + f = -8*d for d.

A: -2
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Q: Let r(s) = s + 6. Let i be r(4). Suppose x = -8 + i. What is the highest common divisor of x and 4?

A:
2
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