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: Calculate prob of sequence tw when two letters picked without replacement from {t: 5, p: 1, y: 6, w: 4, h: 1, s: 3}.

A: 1/19
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Q: -4*80.8

A: -323.2
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Q: Convert 25.14383 millennia to years.

A:
25143.83
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