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: Solve 5*c = 3*z - 31, 0*c + c + 7 = z for c.

A: -5
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Q: Solve 3*x = t + 11, 2*x = 3*x + 4*t - 21 for x.

A: 5
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Q: Calculate 2 + 2 - (-16 - -16).

A:
4
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