instruction:
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).
question:
Calculate prob of sequence rkk when three letters picked without replacement from {r: 12, k: 3}.
answer:
12/455


question:
Add together -0.1 and 637.
answer:
636.9


question:
Calculate prob of picking 1 b and 1 h when two letters picked without replacement from {o: 10, z: 3, h: 2, b: 5}.
answer:

1/19