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 Input:
Suppose -u = -7 + 1. What is the remainder when 17 is divided by u?

Ex Output:
5


Ex Input:
Solve 56 - 20 = -3*i - 4*w, 5*i + 4*w = -44 for i.

Ex Output:
-4


Ex Input:
Let r(j) = -17*j - 3. Suppose 4*c = -4*v - 36, 5*v - v - 4 = 4*c. Let a be r(v). Calculate the greatest common factor of 26 and a.

Ex Output:

13