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 ppy when three letters picked without replacement from {y: 2, p: 2}.
[A]: 1/6


[Q]: Two letters picked without replacement from {u: 1, q: 2, x: 1, s: 2, k: 2, m: 4}. Give prob of picking 1 s and 1 m.
[A]: 4/33


[Q]: Let y be ((-100)/15 + 4)*-3. What is the highest common factor of 20 and y?
[A]:
4