Answer:
D
Step-by-step explanation:
They didn't provide the number for one of the faces btw..
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 ![E[L]=1.375n](https://tex.z-dn.net/?f=E%5BL%5D%3D1.375n)
.
By definition of variance, we have
![\mathrm{Var}[L]=E\left[(L-E[L])^2\right]=E[L^2]-E[L]^2](https://tex.z-dn.net/?f=%5Cmathrm%7BVar%7D%5BL%5D%3DE%5Cleft%5B%28L-E%5BL%5D%29%5E2%5Cright%5D%3DE%5BL%5E2%5D-E%5BL%5D%5E2)
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 ![\mathrm{Var}[L]=1.859n](https://tex.z-dn.net/?f=%5Cmathrm%7BVar%7D%5BL%5D%3D1.859n)
.
21.6 miles per gallon
Multiplied by 6.2 gallons
21.6 * 6.2 = 133.92
Cheryl can travel 133.92 (or about 134) miles on 6.2 gal. of gas.
Hope that helped!
Answer:
1
Step-by-step explanation:
-2(x-4)+1=7
First Distribute the -2.
-2x+8+1=7
Subtract the 8 and 1 from the whole equation.
-2x=-2
Divide both sides of the equation by -2.
x=1
I hope this helps!
