Your SRAT puzzle is the greatest. Definitely my all-time favorite. Since I see you posted a few solutions I give my route to the answer. Thanks for making this!! Brian Doyle brian@balance-software.com 1a no: if 1a then 1b (a contradiction) 1b no: if 1b then 2 has the first b (a contradiction) 2b no: by 1b by 1, min B is 1 by 3, min E is 0, max E is 4 by 4, min A is 4, max A is 8 3 has a single solution 4 has a single solution 5e, yes: self-referential question 3a no: by 5e min E is 1: by 3a 6a, no: because if yes, 17c would be A 6c, no: because if yes, 17e would be C 6e, no: because 6a & 6c are no, plus contradiction by 6d 6 has single solution by 6b and 6d 17a, no: because if yes, 6c would be A 17c, no: because if yes, 6e would be C 17e, no: because 17a & 17c are no, plus contradiction by 17d 17 has single solution by 17b and 17d 7e no: by 2b 8a no: min A + min E by 8, min vowels is 5, max vowels is 8 10a: yes: by 16d 10b,c,d,e no: by 10a (answers must be unique) 16d: yes: by 10a 16a,b,c,e no: by 16d 11a no: by 1, min B 1a no: 3a no: 5a no: 7a no: 19a no: by 13 13a no: if 13a, then 9a (2 odd answers, contradicts 13) 13b no: by 11a 13c no: if 13c then 13a 13e no: by 17a 13d yes: single solution by 14, min D is 6, max D is 10 12c no: 15 implies 12 has single solution, if 12c then ( 12a or 12b ) 12d no: 15 implies 12 has single solution, if 12d then 12b 12e no: 15 implies 12 has single solution, if 12e then 12b 15c no: by 12c 15d no: by 12d 15e no: by 12e 2e no: 10a is not equal to 11a 5b no: 2e is not equal to 5e 1e no: by 5b 17d no: by 2, 16d, single solution 17b yes: only choice by 17b, min B is 2 16d yes: 17b 16b no: 16d, single solution by 1c, 1d, 2, and single solutions, either 3 is only B or 4 is only B but not bo th 4e no: if 3 is B, then 4 is A, C, or D (by max vowels). otherw ise 4 is B. 3e no: if 4 is B, then 3 is either C or D (by max vowels) 5c no: 3e is not equal to 5e 5d no: 4e is not equal to 5e 11e no: at most only 3 B's in rows 1-10 18d no: min A is greater than max E 9b no: if 9b then at least two B's in 1-10, contradicting 11b 9c no: if 9c then 12c == yes 11d no: at most 2 B's in 1-10 14e no: only 9 possible D's: 1-4 have single solutions, so by 2 only 2 possib le (2) 1 at 6 (3) 7-9 have single solutions, so by 2 only 2 possib le (5) 13-4 have single solutions, so by 2 only 1 possi ble (6) 1 at 16 (7) 1 possible at 19 (8) 1 possible at 20 (9) by 14e, max D is 9 9e no: 14e 4d no: let there be 7 A's (1 odd, 6 even). Then 4a is a contra diction. 4c no: let there be 6 A's (1 odd, 5 even) which gives 4c. Then we have 2a which gives 7d, thus 8 must be c or e. since 4 is c by 1 we have 3b, therefore we have 7 vowels, which contr adicts both 8c and 8e. 18c no: max A is 5 14d no: by 13d, 2, single solution 15a yes: 13d 15b no: 15a, single solution 12a yes: 15a 12b no: 12a 9a no: 13, 15a 9d yes: single solution, 13d 2d no: 9a, 10a 4a no: if 4a (4 A's), then 3b and 8b. if 8b then 2a (5 A's), a contradiction. 4b yes: single solution 3b no: 4b, 2, single solution 1d yes: 4b 1c no: single solution by 3b, min E is 2, max E is 3. min vowels is 7, max vowels is 8 8b no: min vowels is 7 8c no: min vowels is 7 2c no: if 2c, then 8d giving 3c which contradicts 2 2a yes: single solution 7d yes: 2 7b no: 7c no: 2, 6 8c no: 2, 7d, 9d 8d yes: 8, single solution 3c no: 8d, 4b 3d yes: 8d, 4b 11b yes: 1-10b 11c no: 11b, single solution 14a no: 1-18d 18b no: max 3 C's // At this point, an answer to 20 needs to be given to settle 14 and 18. The // choice E is the most appropriate from a subjective point of view (and leads // ultimately to the "correct" solution), but it is possible to pick another // choice for 20 (that in a sense is no less correct) and bring the puzzle to // a state where all 20 answers are consistent even though the right "solution" // (i.e. the one the author had in mind) isn't achieved. The author states // as much in the problem description. 20e yes: Standardized test has nothing to do with intelligence, n or do temperature, wind-velocity, latitude, and lon gitude have (equally) anything to do with barometer. The ra tionale for another choice in 20 is "if barometer has nothin g to do with all of them, then it might as well have nothing to do with any of them", so any answer is potentially corre ct. Another observation might be that "standardized test" re lates to "intelligence" in that both phrases have the sam e number of letters when the four letter word is removed. S ince "barometer" and "longitude (only)" have the same number of l etters when the four letter word is removed we might also co nclude that D is the best choice. Anyhow, picking 20e leads to the obvious "author's choice" solution: 20a no: 20b no: 20c no: 20d no: single solution for 20 18a yes: 4b 18e no: single solution, 18a 14b yes: 18a 14c no: 14b, single solution 19b yes: 14b 19c no: 19d no: single solution, 14b now the letters in order spell out "dad bedded a bad bad babe" this is a reference to the movie "Fatal Attraction"