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:
What is -7.84 - -0.0455?
answer:
-7.7945


question:
Let a(q) = q**3 - 13*q**2 + 12*q + 13. Let n be a(12). Let p(x) = 2*x - 13. What is the units digit of p(n)?
answer:
3


question:
Three letters picked without replacement from {e: 4, z: 1, r: 9}. What is prob of picking 3 r?
answer:

3/13