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Occultation vs. transit vs. eclipse

Problem

Planetary alignment occurs when two or more planets form a line with the sun, sometime during their respective orbits.
So consider approximately how long the following planets take to revolve around the sun...
  • Mercury: 1/4 Earth Year
  • Venus: 2/3 Earth Year
  • Earth: 1 Earth Year
  • Mars: 2 Earth Year
Assuming the planets start in an aligned state, how many revolutions will it take each planet before they are aligned again in the same position?
PlanetRevolutions
Mercury
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0.75
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
Venus
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0.75
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
Earth
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0.75
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
Mars
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0.75
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
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