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: Let d be (0 + -33)*(-21)/9. Let k be (10 - 4)/(2/3). Let j be -4*3/(-6) + k. Calculate the highest common divisor of j and d.

A: 11
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Q: Suppose -u = 3*w - 10, -3*w = -4*w - 2*u. Suppose -w*d + 15 = 3. Solve o = -d*o + 16 for o.

A: 4
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Q: How many years are there in 21/5 of a century?

A:
420
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