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).
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Question: Let w = -12 - -21. Let n = w + -5. Suppose 0 = -2*p + 6, 5*l - 38 = -0*l + n*p. Calculate the least common multiple of l and 5.

Answer: 10


Question: Let k = 5811/122 - 8/61. Let l = 2143/345 + -34/23. Let r = l + -13/45. Calculate the common denominator of k and r.

Answer: 18


Question: Solve 87*z = 121*z - 340 for z.

Answer:
10