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Dialling a telephone number an old man forgets the last two digits remembering only that these are different dialled at random. The probability that the number is dialled correctly is `1//45` b. `1//90` c. `1//100` d. none of these

A

`1//90`

B

`81//91`

C

`2//99`

D

none of these

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The correct Answer is:
A
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