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: Suppose 60*x + 70 = 65*x. Calculate the highest common factor of x and 21.

A: 7
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Q: Solve 154 = -39*v - 41 for v.

A: -5
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Q: Two letters picked without replacement from {m: 3, f: 1, o: 1, c: 2, z: 5, i: 1}. What is prob of sequence zo?

A:
5/156
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