One boy forgot the last digit of a 7 digit telephone no. If he randomly dialthe final 3 digits after correctly dialing the 1st four, then what is the chance of dialing the correct no.? Choose the correct choice from the following:
A) 1/500	B) 2/455	C) 1/1000	D) 3/1000	E) 4/1000
it is given that last 3 digits are randomly dialed   Then, each of the digit can be selected out of 10 digits in 10 ways. Hence, required probability   = 1/(10)3 = 1/1000   1/1000
<result>C</result>
One boy forgot the last digit of a 7 digit telephone no. If he randomly dialthe final 3 digits after correctly dialing the 1st four, then what is the chance of dialing the correct no.?