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]: Solve 0 = -4*v + 2*z + 18, 4 = 3*v + z - 7 for v.
[A]: 4


[Q]: Let y be (1 - -1)/(-1) + -25. What is the common denominator of 117/10 and (y/(-30))/((-9)/(-111))?
[A]: 10


[Q]: 27/18 - (-78)/(-12)
[A]:
-5