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 Q]: Solve 96*r - 13 = 91*r + 2*u, 3*u - 12 = -3*r for r.
[EX A]: 3

[EX Q]: Suppose -s = 4*r - 45, -s - r + 4*r = -38. Calculate the remainder when 121 is divided by s.
[EX A]: 39

[EX Q]: Let d(l) = l**2 - 3*l. Let x = 2 + 0. Suppose -x*b + 13 = 1. Calculate the remainder when d(5) is divided by b.
[EX A]:
4