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: Convert 5396.8g to nanograms.
Example Output: 5396800000000

Example Input: Suppose p - 4*p = 0. Suppose -4*v + 0*v + 17 = -l, 4*l + 4 = p. Suppose -3*m + 55 = -17. Solve -5*r + v = m for r.
Example Output: -4

Example Input: Evaluate 2 + 21/5*-1 - -2.
Example Output:
-1/5