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 2*s - 2*z = 18, -4 = -2*s - z - 1. Suppose -v + 9 + 6 = -s*o, 17 = 3*v + 2*o. What is the units digit of v?

A: 7
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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: Suppose 633 = 4*h - 11. What is the greatest common divisor of 23 and h?

A:
23
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