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: What is prob of picking 4 y when four letters picked without replacement from yyyyyyyymmmymm?

A: 18/143
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Q: Two letters picked without replacement from {t: 1, z: 1, v: 1, b: 1, s: 1, p: 2}. What is prob of picking 1 t and 1 p?

A: 2/21
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Q: Four letters picked without replacement from {b: 1, s: 11, w: 1}. What is prob of sequence ssbw?

A:
1/156
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