Problem of the week


Rumours spread at an amazing speed. Suppose that you get hold of a fat,

juicy rumour and that in next 5 minutes they, in turn, go out and tell it to two other people.

Within the next five minutes they in turn go out and tell it to two others. And so on ;

each person who hears the story tells it to two others within the next five minutes.

How many people know the secret within two hours ?


Send your solution by 15 Oct 2017 on

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