Subject
Quantitative Aptitude
Topic
Probability
I forgot the last digit of a 7-digit telephone number. If 1 randomly dial the final 3 digits after correctly dialing the first four, then what is the chance of dialing the correct number?
I forgot the last digit of a 7-digit telephone number. If 1 randomly dial the final 3 digits after correctly dialing the first four, then what is the chance of dialing the correct number?
ক)
1/999খ)
1/1001গ)
1/1000ঘ)
4/1000Explanation
It is given that last three digits are randomly dialled. then each of the digit can be selected out of 10 digits in 10 ways. Hence required probability = = 1/1000Related questions
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