Class 11MathematicsPermutations and CombinationsDefinition of permutation, Number of permutations with or without repetition, Conditional permutations
EasyWhile dialing a telephone number,an old man forgets the last two digits,remembering only that these are different. If he dials the last two digits at random,what is the probability that the number is dialed correctly?
- A$\frac{1}{45}$
- B$\frac{1}{90}$
- C$\frac{1}{100}$
- DNone of these
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