Perms question (1 Viewer)

[enigma_1]

In morse code, letters are formed by a sequence of dashes and dots. How many different letters is it possible to represent if a maximum of ten symbols are used?

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ANSWER: 2046

 

[HSC2014]

Consider the cases where 1,2,3...10 symbols are used:
2 + 2^2 + 2^3 + ... + 2^10 = 2046

 

[hit patel]

Yes this is a Cambridge question right? It basically what HSC 2014 said. This is because there are 10 ways that the sequences can be arranged in which there are 10 exponential possibilities and there are 2 possibities of the symbol.