Answer:
Step-by-step explanation:
Assume that f(x) = 0 for x outside the interval [4,7]. We will use the following
![Var(X) = E[X^2]- (E[X])^2](https://tex.z-dn.net/?f=Var%28X%29%20%3D%20E%5BX%5E2%5D-%20%28E%5BX%5D%29%5E2)
Standard deviation = ![\sqrt[]{Var(X)}](https://tex.z-dn.net/?f=%20%5Csqrt%5B%5D%7BVar%28X%29%7D)
Mean =
Then,
![E[X] = \int_{4}^{7}\frac{1}{3}dx = \frac{7^2-4^2}{2\cdot 3} = \frac{11}{2}](https://tex.z-dn.net/?f=E%5BX%5D%20%3D%20%5Cint_%7B4%7D%5E%7B7%7D%5Cfrac%7B1%7D%7B3%7Ddx%20%3D%20%5Cfrac%7B7%5E2-4%5E2%7D%7B2%5Ccdot%203%7D%20%3D%20%5Cfrac%7B11%7D%7B2%7D)
![E[X^2] = \int_{4}^{7}\frac{x^2}{3}dx = \frac{7^3-4^3}{3\cdot 3} = 31](https://tex.z-dn.net/?f=E%5BX%5E2%5D%20%3D%20%5Cint_%7B4%7D%5E%7B7%7D%5Cfrac%7Bx%5E2%7D%7B3%7Ddx%20%3D%20%5Cfrac%7B7%5E3-4%5E3%7D%7B3%5Ccdot%203%7D%20%3D%2031)
Then, 
Then the standard deviation is ![\frac{\sqrt[]{3}}{2}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Csqrt%5B%5D%7B3%7D%7D%7B2%7D)
Answer:
The answer is 240 m^3.
Step-by-step explanation:
1.. 100 divided by 100 is 1.
Answer:
(-4,-2)
Step-by-step explanation:
Answer:
It would be 1/34 or 1/16.
Step-by-step explanation:
Add up how many kids there are in total and then see how many girls there are and write it like this: 18/34. Since it says a girl then you would do it as 1/34 or 1/16 it depends on how you look at it and or how you understand what the question is talking about.