If you flip a fair coin 3 times, what is the exact probability that you will get at least two heads in a row?
3/8
The 8 possible outcomes are HHH, HHT, HTH, HTT, THH, THT, TTH, TTT. The outcomes containing at least two consecutive heads are HHH, HHT, THH (3 out of 8).
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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