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:
Solve -5*i - 5*r - 50 = 0, -r + 5 = -4*i - 10 for i.

Ex Output:
-5


Ex Input:
Solve -4*f = 3*o - 3 + 4, 2*o - 3*f - 5 = 0 for o.

Ex Output:
1


Ex Input:
What is prob of picking 1 q and 1 z when two letters picked without replacement from qqzqqqqzq?

Ex Output:

7/18