Answer: E(Y) = 1.6 and Var(Y)=1.12
Step-by-step explanation:
Since we have given that
X 0 1 2
P(X) 0.4 0.4 0.2
Here, number of games = 2
So, 
Since 
are independent variables.
so, ![E[Y]=2E[X]\\\\Var[Y]=2Var[X]](https://tex.z-dn.net/?f=E%5BY%5D%3D2E%5BX%5D%5C%5C%5C%5CVar%5BY%5D%3D2Var%5BX%5D)
So, we get that
![E(X)=0.4\times 0+0.4\times 1+0.2\times 2=0.8\\\\and Var[x]=E[x^2]-(E[x])^2\\\\E[x^2]=0\times 0.4+1\times 0.4+4\times 0.2=1.2\\\\So, Var[x]=1.2-(0.8)^2\\\\Var[x]=1.2-0.64=0.56](https://tex.z-dn.net/?f=E%28X%29%3D0.4%5Ctimes%200%2B0.4%5Ctimes%201%2B0.2%5Ctimes%202%3D0.8%5C%5C%5C%5Cand%20Var%5Bx%5D%3DE%5Bx%5E2%5D-%28E%5Bx%5D%29%5E2%5C%5C%5C%5CE%5Bx%5E2%5D%3D0%5Ctimes%200.4%2B1%5Ctimes%200.4%2B4%5Ctimes%200.2%3D1.2%5C%5C%5C%5CSo%2C%20Var%5Bx%5D%3D1.2-%280.8%29%5E2%5C%5C%5C%5CVar%5Bx%5D%3D1.2-0.64%3D0.56)
So, E[y]=2×0.8=1.6
and Var[y]=2×0.56=1.12
Hence, E(Y) = 1.6 and Var(Y)=1.12
Answer:
Step-by-step explanation:
x= money earned per hour working as a cashier.
y=money earned per hour working delivering newspapers.
We propose the following system of equations:
5x + 4y =77
6x + 3y=78
We solve the system by reduction method:
-6*(5x+4y=77) ⇒ -30x-24y=-462
5*(6x+3y=78)⇒ 30x+15y=390
---------------------------
-9y=-72 ⇒ y=-72 /-9=8
Now, we get the value of "x" replacing the value of "y" by "8" in any part of the equation above.
5x + 4(8)=77
5x+32=77
5x=77-32
5x=45
x=45/5=9
therefore;
money earned per hour working as a cashier= $9/ hour
money earned per hour working delivering newspapers=$8/hour
Answer:
h = 2.5
Step by step explanation:
We have been given an equation 
that models the total miles Michael traveled one afternoon while sledding, where u equals the number of hours walking up a hill and (u – 2) equals the number of hours sledding down the hill.
To find value of u we will solve our equation.
Upon using distributive property we will get,
Now let us add 18 to both sides of our equation.
Now let us combine like terms.
Upon dividing both sides of our equation by 10.5 we will get,
Therefore, value of u is 2.5.
I'm pretty sure it is 4, 10.5/5 = 2.1 and 8.5/2.1 = 4.047619047619048 which to the nearest tenth is 4.0 or 4......hope this helps,and hope it is correct!!
Answer:
210
Step-by-step explanation:
450 X 1/3 = 150
450 X 1/5 = 90
.
90 + 150 = 240
.
450 - 240 = 210
