Answer: There is 1 1/2 times more juice than ginger ale; there is 2/3 as much ginger ale as there is punch.
Step-by-step explanation:
The expected value is
![E[X]=\displaystyle\sum_xx\,P(X=x)=\frac1{11}\sum_{x=0}^{10}x=\dfrac{0+1+\cdots+9+10}{11}=\dfrac{55}{11}=\boxed{5}](https://tex.z-dn.net/?f=E%5BX%5D%3D%5Cdisplaystyle%5Csum_xx%5C%2CP%28X%3Dx%29%3D%5Cfrac1%7B11%7D%5Csum_%7Bx%3D0%7D%5E%7B10%7Dx%3D%5Cdfrac%7B0%2B1%2B%5Ccdots%2B9%2B10%7D%7B11%7D%3D%5Cdfrac%7B55%7D%7B11%7D%3D%5Cboxed%7B5%7D)
The standard deviation is the square root of the variance, which is
![V[X]=E[(X-E[X])^2]=E[X^2]-E[X]^2](https://tex.z-dn.net/?f=V%5BX%5D%3DE%5B%28X-E%5BX%5D%29%5E2%5D%3DE%5BX%5E2%5D-E%5BX%5D%5E2)
where
![E[X^2]=\displaystyle\sum_xx^2\,P(X=x)=\frac1{11}\sum_{x=0}^{10}x^2=\dfrac{0^2+1^2+\cdots+9^2+10^2}{11}=\dfrac{385}{11}=35](https://tex.z-dn.net/?f=E%5BX%5E2%5D%3D%5Cdisplaystyle%5Csum_xx%5E2%5C%2CP%28X%3Dx%29%3D%5Cfrac1%7B11%7D%5Csum_%7Bx%3D0%7D%5E%7B10%7Dx%5E2%3D%5Cdfrac%7B0%5E2%2B1%5E2%2B%5Ccdots%2B9%5E2%2B10%5E2%7D%7B11%7D%3D%5Cdfrac%7B385%7D%7B11%7D%3D35)
so that
![V[X]=35-5^2=10](https://tex.z-dn.net/?f=V%5BX%5D%3D35-5%5E2%3D10)
making the standard deviation
![\sqrt{V[X]}=\sqrt{10}\approx\boxed{3.16}](https://tex.z-dn.net/?f=%5Csqrt%7BV%5BX%5D%7D%3D%5Csqrt%7B10%7D%5Capprox%5Cboxed%7B3.16%7D)
Answer:
x=3 and x=-1
Step-by-step explanation:
If f(x)=g(x), then 2x+3=x^2:
x^2-2x-3=0
(x-3)(x+1)=0
x=3 and x=-1
5/12 of 5 hours is 2.08333333 hours
Answer:
x = 9
Step-by-step explanation:
Simplifying
2 + -6(1 + -1x) = 6 + -4(-1x + -2)
2 + (1 * -6 + -1x * -6) = 6 + -4(-1x + -2)
2 + (-6 + 6x) = 6 + -4(-1x + -2)
Combine like terms: 2 + -6 = -4
-4 + 6x = 6 + -4(-1x + -2)
Reorder the terms:
-4 + 6x = 6 + -4(-2 + -1x)
-4 + 6x = 6 + (-2 * -4 + -1x * -4)
-4 + 6x = 6 + (8 + 4x)
Combine like terms: 6 + 8 = 14
-4 + 6x = 14 + 4x
Solving
-4 + 6x = 14 + 4x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-4x' to each side of the equation.
-4 + 6x + -4x = 14 + 4x + -4x
Combine like terms: 6x + -4x = 2x
-4 + 2x = 14 + 4x + -4x
Combine like terms: 4x + -4x = 0
-4 + 2x = 14 + 0
-4 + 2x = 14
Add '4' to each side of the equation.
-4 + 4 + 2x = 14 + 4
Combine like terms: -4 + 4 = 0
0 + 2x = 14 + 4
2x = 14 + 4
Combine like terms: 14 + 4 = 18
2x = 18
Divide each side by '2'.
x = 9
Simplifying
x = 9