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).

[Q]: In base 9, what is -356 + -2?
[A]: -358


[Q]: Convert 39.12191 tonnes to milligrams.
[A]: 39121910000


[Q]: Let i = -28 - -30. Suppose 4*z + 5*k = 200, -i*z + 81 = -k - 33. What is the tens digit of z?
[A]:
5