TASK DEFINITION: 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).
PROBLEM: Solve 0 = 4*y + 5*t - 15, 17 = 4*y - t + 4*t for y.

SOLUTION: 5

PROBLEM: What is next in -63, -68, -75, -84, -95, -108?

SOLUTION: -123

PROBLEM: Let u be -3*(-6)/(-4)*2. Let w(d) = -d**2 - 9*d + 2. Let f be w(u). Solve 3*x - f*y = -0*y + 6, y = x - 1 for x.

SOLUTION:
4