You flip a fair two-sided coin three times in a row. What are the exact odds, expressed as a simplified fraction, that you will land on heads at least twice?
1/2
There are 8 total outcomes (2^3). The outcomes with at least two heads are HHH, HHT, HTH, and THH (4 outcomes). 4/8 simplifies to 1/2.
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: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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