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: Solve 3*q - 9 = -3*s + 5*s, -q + 3 = -3*s for q.

Answer: 3


Question: Let t be 4 + -2 + 1/1. Let z = -1 + t. Solve z*q - q = 0 for q.

Answer: 0


Question: What is prob of sequence ttr when three letters picked without replacement from ttttrrtt?

Answer:
5/28