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? Choose the correct choice from the following
A) 1/1002
B) 1/1028
C) 1/1000
D) 1/1287
E) 1/1289
Explanation:   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 = = 1/1000   Answer: 1/1000) 1/1000
<result>C</result>
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?