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).

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

Three letters picked without replacement from {e: 6, k: 1, f: 5, o: 7}. What is prob of picking 1 o and 2 e?
35/323

What is next in -63, -100, -163, -264, -415, -628?

-915