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).

[EX Q]: Calculate prob of sequence woq when three letters picked without replacement from woqcvkc.
[EX A]: 1/210

[EX Q]: Let o(v) = -v**3 - 3*v**2 - 4*v - 6. Let u be o(-4). Suppose 3*q + 11 - u = 0. Solve -5*p = f - 4*p - 6, -3*f + 26 = q*p for f.
[EX A]: 2

[EX Q]: Let z(f) = -209*f - 2. What is the tens digit of z(-1)?
[EX A]:
0