Dialing a telephone number, an old person forgets last three digits. Remembering only that these digits are different, he dialed at random. What is the chance that the number dialed is CORRECT?

Dialing a telephone number, an old person forgets last three digits. R

1.	Dialing a telephone number, an old person forgets last three digits. Remembering only that these digits are different, he dialed at random. What is the chance that the number dialed is CORRECT?
A.	\(\frac{1}{1000}\)
B.	\(\frac{1}{720}\)
C.	\(\frac{9}{70}\)
D.	\(\frac{1}{7840}\)
Answer» C. \(\frac{9}{70}\)

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Dialing a telephone number, an old person forgets last three digits. Remembering only that these digits are different, he dialed at random. What is the chance that the number dialed is CORRECT?

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