Question 9
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Seven-digit phone numbers must begin with 9 and have no repeated digit. How many such numbers are there?
- A 5,31,441
- B 84
- C 60,480 Correct
- D 3,62,880
Correct Answer: Option C
First digit fixed as 9
Remaining 6 places from the other 9 digits: 9P6 = 60,480
Trap: 5,31,441 = 9⁶ allows repeats.
Answer: 60,480
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