Question

N persons are standing in a circle. They are labelled from 1 to n in clockwise order. Every one of them is holding a gun and can shoot a person on his left. Starting from person 1, they starts shooting in order e.G for n=100, person 1 shoots person 2, then person 3 shoots person 4, then person 5 shoots person 6..Then person 99 shoots person 100, then person 1 shoots person 3, then person 5 shoots person 7and it continues till all are dead except one. Whats the index of that last person ?

Answer 1

Answer:

73

Step-by-step explanation:

n start from 0

1  , 2  ,  3 , ............................................, 99 , 100  n  (  n = 100)

1 ,  3 , 5  , ...............................................97 , 99   (2n-1)  (n = 50)

1  , 5  , 9  , ........................................... 93 , 97     (4n -3 ) (n = 25)

1  , 9  , 17  ,............................................, 89 , 97   (8n -7)  (n = 13)

9  ,  25 ,..............................................., 89                (16n - 7) (n = 6)

9  ,  41  , 73               (32n - 23) (n = 3)

9 , 73     (64n - 55)

73