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: Four letters picked without replacement from rsisririrsshs. What is prob of sequence iirr?
Example Output: 3/715

Example Input: Suppose -3*x - 2*x = 0. Suppose 0 = -2*j + 3*v - 8, 2*j - 2*v + 4 = -x*v. What is the units digit of j?
Example Output: 2

Example Input: How many milligrams are there in twenty-five quarters of a gram?
Example Output:
6250