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 17 = -v + 2*f + 1, 0 = 5*v - 3*f + 52. Let i be ((-12)/v + -2)*-4. What is the greatest common divisor of 4 and i?

A: 2
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Q: Let n(s) = s**2 + 3*s + 2. Let z be n(-2). Suppose z = j + j - 70. Suppose -j - 56 = -t. What is the highest common factor of 13 and t?

A: 13
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Q: How many millilitres are there in 3/25 of a litre?

A:
120
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