Show I Vs £ in IY MARILYN YDS SAVANT tint let me explain why your answer is wrong The winning odds of 13 on the first choice can’t go up to 12 m b a or just because the host opens a losing ' door lb illustrate this let's say we play a shell game Yon look away and I put a pea under one of three V shells Then I ask you to put your V finger on a shell The odds that your choice contains a pea are 13 agreed? Then I simply lift up an empty shell fixxn die remaining two As I can (and will) do this regardless of what you've chosen we've learned nothing to allow us to revise the odds an the : vv shell under your finger see benefits of swnqhhtg The readily ptpvod by playing through the six games thk exhaust all the possibilities For die first three games you dioose No l and switch each time for the second three games you dioose No 1 and “stay” each time and the host always opens a loser Here are die results (each row is a game): - MM tlM ethers ara pnCmliMl MhomaHeM hi very t CMMMiiHlbtMnlpMA bckefMhOSHtlcdsldfcPleMe hlP bp CMNPbmfMV bikaUM PflNf i ' ! DOOR 2 V DOOR1 AUTO - : GOAT- - W ? Switch and you lose GOAT AUTO Switch and you win goat goat Switch and you win DOOR 3 GOAT v- r GOAT 7 V - auto Cv-:-'- GOAT :: AUTO u1 Stay and you win GOAT GOAT AUTO Stay and you lose 7 GOAT AUTO GOAT and Stay youlose When you switch you win two out time in fifthly rim and lore time but when you don’t switch you only win one in dote times and lose : two in three Tty it yourself Alternatively you actually can day the game with another person acting as the host with duee playiqg carda-- 7 two joken for the goats and an ace for thewto However doing this a few hundred times to get statistically valid results can get a hide tedious so r perhaps you can assign it for extra credit—or for punishment! (ThafU ' 'v ' get dieir goats!) goat r ' ' Good heavens! With so much learned bet this one ia going opposition to keep math classes all over the " country busy on Monday But correct answer is My original m - : i all i‘ i -- If you have a question for Marilyn vos Savant who it lilted in the “Guinness Book pfWorld Records Hall cfFamefor “Higkest IQ" send it to: Ask Marilyn PARADE 750 Third Ave New York NX 10017 Became of volume of mail personal replies are not possible f 4'- -- rf |