JEE MATHEMATICS MCQ: PERMUTATIONS

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The lock of a safe consists of five discs each of which features the digits 0, 1, 2, … ,9.The safe can be opened by dialing a special combination of the digits. The number of days sufficient enough to open the safe. If the work day lasts 13 h and 5 s are needed to dial one combination of digits is

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Correct option: C

Option C (11) is correct because calculating the total time to try all combinations and dividing by the workday length results in approximately 11 days.

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