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3/1/2017 3:17:53 PM

myq8472
myq8472
Posts: 6
I need help with Logic Problems. The last magazine I had, had me so frustrated. All of the clues just had negative answers. There was not one positive answer. How do you work with a puzzle like that? There must be a way. I was wondering if anyone had any advice when it came to these types of puzzles. Thanks.

3/2/2017 10:13:34 AM

Amy Lowenstein
Amy Lowenstein
Posts: 1599
I know what you mean. I think you mean there are all "negative clues," such as "John does not have blond hair." Sometimes, eventually, you get enough negative clues on the same item (such as "John" in my example) that there's only one thing left, so by elimination, that's the answer.

Other times, you wind up with, say, that John can't be blond or black hair, and the person who gets the Times newspaper can't be red, gray or white hair (leaving only blond or black as Times's possibilities) so that implies that John doesn't get the Times.

I hope this helps a little bit.

If you can quote the whole puzzle, including the introduction (because one in a while I ignore the introduction, to my peril!) maybe I can see if I wind up with SOMETHING positive.

--
Amy

3/2/2017 1:22:54 PM

myq8472
myq8472
Posts: 6
Thanks for your response Amy, but what I am referring to, is that I started a puzzle this month. After put in the clues, there wasn't one positive answer to work off of. They were all negative. The puzzle by the way was #19 from the April edition.
The puzzle is Let's Do Brunch, where you have to determine each student's omelet, meat, fruit and drink.
1) says Neither the student who ate blueberries (who didn't drink soda) nor the one who had a side of bacon is the student who ordered a Greek omelet. Blake (who isn't the student who ordered Corned Beef Hash) didn't order strawberries.

the clues go on in this way, with no positive clue given to work off of. When I was done with all the clues, my chart was all negatives. I just didn't know how to begin to solve this puzzle.
edited by myq8472 on 3/2/2017

3/2/2017 4:35:07 PM

Semipro
Semipro
Posts: 292
myq8472 wrote:
1) says Neither the student who ate blueberries (who didn't drink soda) nor the one who had a side of bacon is the student who ordered a Greek omelet. Blake (who isn't the student who ordered Corned Beef Hash) didn't order strawberries.

Okay, so your chart is full of symbols that mean negations such as "blueberries NOT soda" and "blueberries NOT bacon" and "blueberries NOT Greek" and "bacon NOT Greek." At this stage, I would look for something that's mentioned many times. From Clue 1, it might be blueberries, as blueberries are (negatively) linked to three things. But a clue I haven't seen may be a better place to start. Then go through the clues and the chart in a way consistent with Amy's example about John's hair color. See what inferences you can make by combining information from different clues. Sure enough, this kind of cluing makes a puzzle harder than one that says outright that Mary ate grapefruit.

3/2/2017 4:38:23 PM

Amy Lowenstein
Amy Lowenstein
Posts: 1599
myq8472 wrote:
Thanks for your response Amy, but what I am referring to, is that I started a puzzle this month. After put in the clues, there wasn't one positive answer to work off of. They were all negative. The puzzle by the way was #19 from the April edition.
The puzzle is Let's Do Brunch, where you have to determine each student's omelet, meat, fruit and drink.
1) says Neither the student who ate blueberries (who didn't drink soda) nor the one who had a side of bacon is the student who ordered a Greek omelet. Blake (who isn't the student who ordered Corned Beef Hash) didn't order strawberries.

the clues go on in this way, with no positive clue given to work off of. When I was done with all the clues, my chart was all negatives. I just didn't know how to begin to solve this puzzle.
edited by myq8472 on 3/2/2017


I no longer have a subscription to logic magazines, so I haven't seen this particular puzzle. But in general, if I see that "neither" the one who ate blueberries nor the one who had bacon, had a Greek omelet, then I know a few negatives (and the more "negatives" I know, the better, because at some point all that may be left is an "elimination" answer), namely that the blueberries and the bacon don't go together, that the blueberries and Greek omelet don't go together, and that the bacon and Greek omelet don't go together. Those "neither" clues give you about 3 different "negatives" at once. In this case, the parentheses add one more negative, namely that the soda doesn't go with the blueberries.


When your chart is a bunch of negatives, you may have a couple of choices left for positives, which is better than at the beginning when there are lots of choices for positives.

--
Amy

3/2/2017 8:26:34 PM

myq8472
myq8472
Posts: 6
Thanks Amy and Semipro. you've given me a lot to think over.

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