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Maths Puzzle
6 boys pick a captain by forming a circle then eliminating every n'th boy. The 2nd boy in the counting order can choose n. If he wants to be captain what's the smallest n he should pick?
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- The 2nd boy in the counting order can choose n. If he wants to be captain ,
the smallest n he should pick should be 10. - 12 years agoHelpfull: Yes(2) No(1)
- Let the boys names be A B C D E F and let counting start from A.
Since B decides n,we have to check the elimination sequence for each n and find in which B stays in the end.
for n=1,ABCDEF-BCDEF-CDEF
for n=2,ABCDEF-ACDEF
for n=3,ABCDEF-ABDEF-ABDE-ABE-AE
for n=4,ABCDEF-ABCEF-ACEF
for n=5,ABCDEF-ABCDF-ABCF-ABC-AC
for n=6,ABCDEF-ABCDE-BCDE-BDE-DE
for n=7,ABCDEF-BCDEF-BDEF-BDE-DE
for n=8,ABCDEF-ACDEF
for n=9,ABCDEF-ABDEF-BDEF-DEF
for n=10,ABCDEF-ABCEF-ABEF-ABE-BE-B
thus minimum n is 10
- 12 years agoHelpfull: Yes(1) No(1)
- .................................
- 12 years agoHelpfull: Yes(0) No(2)
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