context: ###List of Questions
  (1) Four letters picked without replacement from {m: 12, w: 3}. Give prob of picking 1 m and 3 w.
  (2) Calculate 4 + -2 + -1 + (2 - -1).
  (3) Let b = 40 + -18. Calculate the least common multiple of 42 and b.
  (4) Solve -2 + 48 = -23*w for w.
  (5) Convert 7.612599 years to decades.
q_1: (1) Four letters picked without replacement from {m: 12, w: 3}. Give prob of picking 1 m and 3 w.
q_2: (2) Calculate 4 + -2 + -1 + (2 - -1).
q_3: (3) Let b = 40 + -18. Calculate the least common multiple of 42 and b.
q_4: (4) Solve -2 + 48 = -23*w for w.
q_5: (5) Convert 7.612599 years to decades.