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There are three ants and three vertices.
So for every ant there are two directions in which an ant can go..
So that means for three ants there will be : 2*2*2 i.e. 8 possibilities.
But, they should not collide.. so either all of these ants should move in clockwise direction or ant-clockwise direction i.e. only 2 possibilities
So probability = 2/8 i.e 1/4
not possible to collide, all should be choose same direction.
2/8
1/4
The answer is 0.5. There are 4 possibilities of ants movement. (Number of ants which start moving in anticlockwise direction/ Number of ants which start moving in an anticlockwise direction) can be either (3:0),(2:1),(2:1), (0:3). Out of these 4 possibilities, there are only two possibilities where there won't be any collision. Hence Prob = 2/4 i.e. 0.5
0
Total chances 8. Required chances 2. Probability is 2/8 =1/4 =0.25
Total possibilities is 8. Required option has only one chance to occurs . Hence probability is 1/8 .
So let’s think this through. The ants can only avoid a collision if they all decide to move in the same direction (either clockwise or anti-clockwise). If the ants do not pick the same direction, there will definitely be a collision. Each ant has the option to either move clockwise or anti-clockwise. There is a one in two chance that an ant decides to pick a particular direction. Using simple probability calculations, we can determine the probability of no collision.
P(No collision) = P(All ants go in a clockwise direction) + P( All ants go in an anti-clockwise direction) = 0.5 * 0.5 * 0.5 + 0.5 * 0.5 * 0.5 = 0.25
P(No collision) = P(All ants go in a clockwise direction) + P( All ants go in an anti-clockwise direction) = 0.5 * 0.5 * 0.5 + 0.5 * 0.5 * 0.5 = 0.25
So let’s think this through. The ants can only avoid a collision if they all decide to move in the same direction (either clockwise or anti-clockwise). If the ants do not pick the same direction, there will definitely be a collision. Each ant has the option to either move clockwise or anti-clockwise. There is a one in two chance that an ant decides to pick a particular direction. Using simple probability calculations, we can determine the probability of no collision.
P(No collision) = P(All ants go in a clockwise direction) + P( All ants go in an anti-clockwise direction) = 0.5 * 0.5 * 0.5 + 0.5 * 0.5 * 0.5 = 0.25
P(No collision) = P(All ants go in a clockwise direction) + P( All ants go in an anti-clockwise direction) = 0.5 * 0.5 * 0.5 + 0.5 * 0.5 * 0.5 = 0.25