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 -5*b = -4*l - 14, 3*b + 4 = 6*b + 2*l. Let c(a) be the second derivative of a**3/6 - 2*a**2 + a. What is the remainder when c(7) is divided by b?

Ex Output:
1


Ex Input:
Four letters picked without replacement from arkkallleaakkkra. What is prob of sequence lkak?

Ex Output:
5/728


Ex Input:
Suppose 0 = -0*f - 3*f + 48. Suppose 3*o + 2*y = f, 5*y + 10 = 3*o + 4*y. What is the units digit of o?

Ex Output:

4