21 picks
altogether (2x+5x)=21
7x=21
x=3
2*3=6 orange picks
or
x=orange, y = greens
x+y=21
x/y=2/5,----> y=5x/2
x+5x/2=21
2x/2+5x/2=21
7x/2=21
7x=42,
x=6 orange picks
3.8 x 10²
im pretty sure thats scientific notation
The expected length of code for one encoded symbol is
where is the probability of picking the letter , and is the length of code needed to encode . is given to us, and we have
so that we expect a contribution of
bits to the code per encoded letter. For a string of length , we would then expect .
By definition of variance, we have
For a string consisting of one letter, we have
so that the variance for the length such a string is
"squared" bits per encoded letter. For a string of length , we would get .