SOLUTION: Morse code for the alphabet consists of dots and dashes. Each symbol contains between 1 and 4 dots and dashes. How many different symbols can be made? I have tried writing all

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Question 412809: Morse code for the alphabet consists of dots and dashes. Each symbol contains between 1 and 4 dots and dashes. How many different symbols can be made?
I have tried writing all possibilities (too many). Also tried using 4!2!, but don't think that is right.
Thank you in advance for your help!

Found 2 solutions by richard1234, Alan3354:
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
No need to write all the possibilities. Do it case by case (it's easier to count it this way)

Case 1: A letter consists of one "character."

This leaves two possibilities, so 2.

Case 2: A letter consists of two characters.

There are two possibilities for each position, so 4.

The other cases (3 and 4 characters) imply 8 and 16 possibilities (by using a simple induction argument), so the total number is 2 + 4 + 8 + 16 = 30.

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
PS Morse code has no upper and lower case, all the numbers are 5 dots/dashes, some characters, such as punctuation use 6 dots/dashes.
... _ _ _ ... is SOS