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#1
06-09-2013, 03:58 AM
 BillsBayou Member Join Date: Mar 2013 Location: New Orleans Posts: 77

This one has two "Or" clues, one "Either" clue, and two relational clues that stand between me and the solution.

Here is the blank:
Logic-Planets-1.gif

Here is where I'm stuck:
Logic-Planets-2.gif

The two relational clues both have exact measurements. This would normally be good, but neither of these clues have values that have available substitutions.

Clues 7 and 8 both mention the same value "Ereph". But there is no linking value on the other side of the OR statement. When I map out all the combinations of these, I don't have any eliminations. That is, all the combinations are available.

I thought of a relationship between clue 5 and clue 9. Clue 9 shows the relationship between EX53 and PL120. It occured to me that Clue 5 shows two potential equivalent values for EX53. If either of these could not match the relationship to PL120, then that would be the elimination. But no. No eliminations can be found.

I've looked for all my usual oversights. I've looked around the corners, looked for complementary exclusion sets, 2x2 sets, but nothing.

At this point in the puzzle, I only have one group of equivalencies: 49LightYears = 650,000 == MKP427. But there are no remaining clues that use any of these values. So I cannot make any substitutions.

I'm hoping there's some technique I have yet to learn for this. I'd hate to find out I've missed something I've already learned.
#2
06-09-2013, 08:40 AM
 2manynames Junior Member Join Date: Sep 2012 Posts: 11

Ereph is either 45 years or 310,000, substitute this for Ereph in the other clue ie. 47 years is either 45 years (impossible) or 295000 or 310000, and then swap over. You will be able to solve all of the distance box.
#3
06-09-2013, 02:23 PM
 BillsBayou Member Join Date: Mar 2013 Location: New Orleans Posts: 77

That fixed it, thanks! That was perfect.

I've learned another solving technique. This one is super twisted.

I'll expand on how this worked out. I like to spell things out and this one twisted my head too much to just "see" it. I'll get it right with practice.

Begin with Clue 7:
Of the planet 45 light years from earth and the exoplanet with a diameter of 310,000 mi., one orbits the star PLC120, and the other is Ereph.

Restate it in terms of Ereph (and simplify the long text a bit):
Ereph is either 45 years or 310,000

Next, let's go to Clue 8:
Of the planet orbiting star VJD 913 and the exoplanet 47 light years from earth, one has a diameter of 295,000 mi. and the other is Ereph.

And restate (and simply wording) the clue in terms of 47 light years:
47 years is either 295,000 or Ereph.

Substitute from above and we get:
47 is either 295,000 or 45 year or 310,000.

Drop the contradiction and get 47 is either 295,000 or 310,000. Put that into the grid.

This wasn't enough for me to solve the puzzle, so, as instructed, I flipped this technique around and began again, but this time with Clue 8.

Restate Clue 8 in terms of Ereph:
Ereph is either VJD 913 or 47 years.

And restate Clue 7 in terms of 45 light years:
45 years is either PLC 120 or Ereph.

Substitute from above:
45 is either PLC 120 or VJD 913 or 47 years.

45 is either PLC 120 or VJD 913.

Plug this into the puzzle. Now there are enough eliminations on the grid to get the other clues to finish the puzzle without any more complicated techniques.

Thanks, 2manynames!
#4
06-11-2013, 09:45 PM
 BillsBayou Member Join Date: Mar 2013 Location: New Orleans Posts: 77

Here's one where a Forced Contradiction can be used:

I don't know if it was the only way to get past a bottleneck, but I saw it early on and decided to use it.

If anyone cannot see it, I'll be happy to explain.

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