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 4*n + 20 = -0*n. Let j = -5 - n. Let m be (60/4)/(1 - j). Calculate the highest common divisor of 15 and m.

A: 15
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Q: How many nanograms are there in 1/4 of a microgram?

A: 250
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Q: What is prob of picking 1 n and 1 f when two letters picked without replacement from {f: 1, n: 2}?

A:
2/3
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