SOLUTION: An automobile license plate consists of three letters followed by four digits. How many different plates can be made if repetions are allowed? If repetions are allowed in the lette

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Question 475193: An automobile license plate consists of three letters followed by four digits. How many different plates can be made if repetions are allowed? If repetions are allowed in the letters but not in the digits?
Found 2 solutions by josmiceli, jorel1380:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
There are 26 letters, so, with repetitions,
There can be +26%2A26%2A26+=+17576+
different arrangements of the 1st 3 letters
Digits 0 through 9 are allowed, so, with repetitions,
There are +10%2A10%2A10%2A10+=+10000+
arrangements of 4 digits.
EACH of these +10000+ ways can be attached
to EACH of the +17576+ arrangements of letters, so
+26%2A26%2A26%2A10%2A10%2A10%2A10+=+175760000+ is
the total number of possible plates

Answer by jorel1380(3719) About Me  (Show Source):
You can put this solution on YOUR website!
3 letters=26^3=17576
4 digits=0000-9999=10000
3 letters by 4 digits=17576x10000=175,760,000
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no repetitions allowed in digits=10C4=10x9x8x7x6!/4x3x2x6!=10x3x7=210
210 x 17576=3690960..