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 -k = -4*a + 15, 0 = 6*k - 10*k + a + 15 for k.

Ex Output:
5


Ex Input:
Solve -2*b + 28 = -5*q, -b - q + 4 = b for b.

Ex Output:
4


Ex Input:
Calculate prob of picking 2 t and 1 h when three letters picked without replacement from khktkhtk.

Ex Output:

1/28