In the city of Brain Teasers, 5% of people do not list their phone numbers. Now if we select random 100 people from the phone directory, then how many people selected will have unlisted phone numbers?
Anabelle is a clever trader of rare artefacts. Each day she carries three boxes each filled with thirty artifacts. The boxes can't hold more than that. She travels far in northern lands to sell these artefacts but on the way, she comes across thirty checkpoints where she has to shed one of the artefacts for each sack to the authorities for letting her pass.
How many artifacts will be left with her when she reaches her destination crossing all the checkpoints?
Three ants are sitting at the three corners of an equilateral triangle. Each ant starts randomly picks a direction and starts to move along the edge of the triangle. What is the probability that none of the ants collide?
