A number lock on a suitcase has three wheels each labeled with ten digits 0 to 9. if opening of the lock is a particular sequence of three digits with no repeats, how many such sequences will be possible? Also, find the number of unsuccessful attempts to open the lock.
The number of sequences possible =10 × 9 × 8=720(since no repeated digits is the given condition.)
There will be only one successful attempt so the number of unsuccessful attempts to open the lock=720-1=719.
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