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Grid Puzzles

Logic puzzles can get complicated, and keeping track of information while you're sleuthing is no easy task. See how grids can help you efficiently deduce your way to the truth.

Elimination Grid - Insufficient Information


Four boys Alex, Bradan, Charlie and David paired up with four girls Amy, Bella, Cindy and Danielle. Alex paired up with Bella, David did not pair up with Amy, and only one of the four couples had names starting with the same letter. If we can determine all the pairings with certainty from this information, who is Cindy's boy?

Four employees of a company Adam, Ben, Carl and David are planning on a \(2\)-week vacation for everyone. Their \(4\) possible departure dates are March \(22,\) March \(29,\) April \(5\) and April \(12,\) and no two employees can leave on the same day. If the following rules determine the departure date for each with certainty, who is "X"?

\(1.\) Adam does not leave the latest.
\(2.\) Ben must not come back on April \(12.\)
\(3.\) Carl leaves earlier than both Ben and David.
\(4.\) Adam leaves a week after "X".

\(7\) free movie tickets were available to the students in a college dorm. Amy, Beth, Cindy and Debra rushed to the management office and took all of the \(7\) tickets. Since each of them talked to the office girl one-to-one, they did not know who actually got the tickets or how many, except for their own. So, they began talking among themselves.

Amy first asked Beth, "Did you get more tickets than I did?"
Beth answered, "I don't know."

Then Beth asked Cindy, "Did you get more tickets than I did?"
Cindy answered, "I don't know."

Upon hearing these, Debra said, "I now know the exact distribution of the \(7\) tickets."

What is the distribution (Amy, Beth, Cindy, Debra) that Debra figured out?

Alex, Brian and Charles bought a dog, cat and fish. If Alex did not buy a dog and Charles did not buy a fish, what can we say about the animal that Brian bought?

\(1.\) He could only have bought the dog or fish.
\(2.\) He could have bought the dog, cat or fish.
\(3.\) He bought the cat.

Note: Alex, Brian and Charles each bought one animal.

Four boys Alex, Bradan, Charlie and Dan paired up with four girls Alice, Bella, Cindy and Danielle. Boys and girls with the same initial letter did not pair up, and Charlie paired up with Bella. If we can deduce the rest of the pairings with certainty, who did Alex pair up with?


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