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]: Suppose -g - 4*g = -3*u + 29, 0 = 4*u + 3*g. Suppose -30 = -4*b - s + u*s, -s - 33 = -4*b. What is the units digit of b?
[EX A]: 9

[EX Q]: Let x be (36/(-20))/((-3)/15). Let r(z) = z**2 - 8*z - 5. Let h be r(x). Solve -k + w + 0 - 2 = 0, -h*k - 2*w + 22 = 0 for k.
[EX A]: 3

[EX Q]: Let k(a) = 0 - 3*a + 0. Let y be k(-2). Let r = -5 + 6. Solve -5*x + y = r for x.
[EX A]:
1