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: Let q be 2/4 - (-438)/4. Let b be 2/(-4) - (-21)/2. What is the greatest common divisor of q and b?

A: 10
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Q: Suppose 0*r = 5*r - 35. What is the units digit of r?

A: 7
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Q: Suppose 2*k - 5 = 5. Suppose -4*a = -5*w + 30, 2*w - w - 15 = -a. Let v = w - 6. Calculate the remainder when k is divided by v.

A:
1
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