An early code used in radio transmission involved using codewords that consist of binary

bits and contain the same number of $1$s$.$ Thus, the $2-$out$-$of$-5$ code only transmits blocks of $5$

bits in which $2$ bits are $1$ and the others $0.$

b$.$ Suppose that the code is used to transmit blocks of binary bits. How many

bits can be transmitted per codeword?

Answer mentioned is : There are $10$ possible codewords. Three bits per codeword can be transmitted if eight codewords are used.

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