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A letter lock consists of three rings ma...

A letter lock consists of three rings marked with 15 different letters . If N denotes the number of ways in which it is possible to make unsuccessful attempts to open the lock, then

A

482 | N

B

N is product of three distinct prime numbers

C

N is product of four distinct prime numbers

D

N is product of two distinct prime numbers

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PATHFINDER-PERMUTATION AND COMBINATION-QUESTION BANK
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