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cos00155079
forming license plate numbers..how many different license plate numbers can be made by using one letter followed by five digits selected from 0 through 9?
counting principle for this one 26 choices for the letter \[10^5=100,000\] for the 5 digit number you get \[26\times 100,000\]
so what formula do i use?
and ewhy 10 to the five power?
The number of different permutations of n different things taken k at a time with repetitions is \[n ^{k}\] In your question the number of digits from 0 ~ 9 is 10 and the digits are taken 5 at a time.