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).
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Question: What is 15/4 of a millisecond in microseconds?

Answer: 3750


Question: Let b(l) = l**3 - 2*l**2 - 3*l. Let g be b(3). Solve g*f + 15 = -3*f for f.

Answer: -5


Question: Let k = -381 - -535. What is the greatest common divisor of k and 14?

Answer:
14