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The code for a particular combination lock can only include
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16 Sep 2020, 13:48
16 Sep 2020, 13:48
00:00
Question Stats:
90% (00:34) correct
10% (02:41) wrong based on 10 sessions
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The code for a particular combination lock can only include letters, symbols, and digits from a selection of 7 letters, 3 digits, and 5 symbols. A valid code for the lock must consist of exactly 2 letters, 1 symbol, 1 digit, and 1 symbol, in that order, and repetition is allowed. How many different codes are possible?
Show: :: OA
3675
Re: The code for a particular combination lock can only include
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16 Sep 2020, 15:51
16 Sep 2020, 15:51
1
#total: 7 letters, 3 digits, and 5 symbols
#needed 2 letters, 1 symbol, 1 digit, and 1 symbol
=> C(7,2) x C(5,1) x C(3,1) x C(4,1)(already chose 1 symbol so 4 left) = 21x5x3x4 = 1260
#needed 2 letters, 1 symbol, 1 digit, and 1 symbol
=> C(7,2) x C(5,1) x C(3,1) x C(4,1)(already chose 1 symbol so 4 left) = 21x5x3x4 = 1260
Re: The code for a particular combination lock can only include
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19 Oct 2020, 02:48
19 Oct 2020, 02:48
1
3675 ways. as repetition is allowed.
