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).

Example Input: Suppose -2*c + 4*j - 30 = 2*j, -5*c = -2*j + 78. Let w be 3/12 + (-12)/c. Solve 2*r = -w - 3 for r.
Example Output: -2

Example Input: Calculate prob of sequence tw when two letters picked without replacement from {t: 5, p: 1, y: 6, w: 4, h: 1, s: 3}.
Example Output: 1/19

Example Input: Evaluate 6/(-28)*1*(-16)/12.
Example Output:
2/7