9000139707 | math4u.vsb.cz

SubArea:

Level:

Project ID:

9000139707

Accepted:

1

Clonable:

0

Easy:

0

A Morse code utilized dots and dashes to encode letters of an alphabet. Find the number of signals of the length from

1

to

4

which can be obtained from dots and dashes.

2 + 2^{2} + 2^{3} + 2^{4} = 30

1 + 2 + 3! + 4! = 33

\frac{4!}{3! 2!} = 2

2 \cdot 1 + 2 \cdot 2 + 2 \cdot 3 + 2 \cdot 4 = 20