7....m I correct????
Nine hundred distinct N digit natural numbers are to be formed using digits 6,8,9 only.Find smallest value of N possible.
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4 Answers
RAY
·2009-09-07 00:54:05
7 digit........
take N =4 suppose...number of distinct number u get is 34.= 81
take N =5 suppose...number of distinct number u get is 35.= 243
take N =6 suppose...number of distinct number u get is 36.=729
take N =7 suppose...number of distinct number u get is 37.= 729*3....hence the answer