Permutations And Combinations Question 197
Question: An n-digit number is a positive number with exactly $ n $ digits. Nine hundred distinct n-digit numbers are to be formed using only the three digits 2, 5 and 7. The smallest value of $ n $ for which this is possible is [IIT 1998]
Options:
A) 6
B) 7
C) 8
D) 9
Correct Answer: B
Show Answer
Answer:
Solution:
BETA
