Logic Brain Teasers: Deduction & Process-of-Elimination

Preview · 10 questions

• 01·Four friends — Anna, Ben, Cara, Dan — sit in a row facing forward. Clues: Ben sits immediately left of Cara. Anna is at one end. Dan is not next to Anna. Who sits at the far right?
• 02·Three children wear hats. Each hat is either red or blue. They see others' hats but not their own. Clues: Alice sees Bob and Carol have blue hats and says 'I don't know my hat.' Bob sees Alice's hat is blue and hears Alice and says 'I don't know either.' Carol, seeing two blue hats, deduces her hat is red. What color is Carol's hat?
• 03·Five days — Mon to Fri — four meetings (A,B,C,D) scheduled, one day empty. Clues: A is before C. B is on Wednesday. D is after C. Which day is empty?
• 04·Three boxes labeled APPLES, ORANGES, MIXED are all incorrectly labeled. You may draw one fruit from one box. From which box should you draw to correctly relabel all boxes?
• 05·Seven runners finished a race. Clues: Tom finished immediately after Rita. Sam finished 3rd. Rita beat Sam. Who finished 2nd?
• 06·Four suspects (X,Y,Z,W) stand in a line. Clues: X is somewhere left of Z. W is immediately left of Y. Z is at the far right. Who is at far left?
• 07·Three colored socks (red, green, blue) are in three drawers labeled R, G, B, but all labels are wrong. You may open one drawer and see one sock. Which drawer do you open to deduce all labels?
• 08·Five people — P,Q,R,S,T — stand in a line. Clues: P is left of R. Q is immediately left of S. T is rightmost. R is immediately left of T. Who is second from left?
• 09·Three boxes contain 1, 2, and 3 balls respectively. Labels say '1', '2', '3' but all labels are wrong. You may pick one ball from one box. From which box should you pick to identify all boxes?
• 10·Four clocks A,B,C,D show times; clues: A shows earlier than B. C shows later than A but earlier than D. B is the latest. Which clock shows the earliest time?