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: Four letters picked without replacement from {u: 9, s: 9}. Give prob of picking 3 s and 1 u.

A: 21/85
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Q: Suppose -16 = l - 18. Solve -4*h + l*h = 0 for h.

A: 0
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Q: Suppose -f = -6*f - v + 29, -28 = -4*f - 2*v. Let d be 1*1/((-3)/(-12)). Suppose d*q = f*m - 0*m + 99, 0 = 5*m + 15. Solve -q = -3*b - 6 for b.

A:
5
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