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: Two letters picked without replacement from {x: 8, p: 5, a: 7}. Give prob of sequence xa.

A: 14/95
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Q: Convert 0.5158104 decades to millennia.

A: 0.005158104
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Q: In base 16, what is -a + 2e1?

A:
2d7
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