Difference between revisions of "2007 iTest Problems/Problem 4"
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Revision as of 20:41, 14 January 2008
Problem
Star flips a quarter four times. Find the probability that the quarter lands heads exactly twice.
Solution
The number of arrangements of the group of letters HHTT is 
, so the probability that two of the flips are heads is 
See Also
| 2007 iTest (Problems, Answer Key) | ||
| Preceded by: Problem 3 |
Followed by: Problem 5 | |
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