I forgot the last three digits of a 7-digit telephone number. If I randomly dial the final 3 digits after correctly dialling the first four, then what are the chances of dialling the correct number?

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Solution

The correct option is A

It is given that last three digits are randomly dialled. Then each of the digits can be selected out of 10 digits in 10 ways. Hence required probability = $\frac{1}{1000}$

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I forgot the last three digits of a 7-digit telephone number. If I randomly dial the final 3 digits after correctly dialling the first four, then what are the chances of dialling the correct number?

The correct option is A It is given that last three digits are randomly dialled. Then each of the digits can be selected out of 10 digits in 10 ways. Hence required probability = 11000

The correct option is A

It is given that last three digits are randomly dialled. Then each of the digits can be selected out of 10 digits in 10 ways. Hence required probability = $\frac{1}{1000}$