Answer:
d) 205
Step-by-step explanation:
<u><em>Step(i):-</em></u>
x : 100 150 200 250 300
p(X=x) : 0.10 0.20 0.30 0.30 0.10
<u>Step(ii):-</u>
Let 'X' be the discrete random variable
Expected value of the random variable
E(X) = ∑ x P(X=x)
= 100 X 0.10 + 150 X 0.20 + 200 X 0.30 +250 X 0.30 + 300 X 0.10
= 205
<u>Final answer:</u>-
The expected value E(X) = 205
Answer:
2 x 10 x 4 + (4 + 10) x 2 x 6 = 80 + 168 = 248
Ok , with that information we can write the equations
x + y = 6
5x + 4y = 28
Where x = how many people ordered chicken
and y = how many people ordered egg salad
Through elimination , we can set one of the variables in both equations equal so we can eliminate it :
(4)x + (4)y = (4)6
5x + 4y = 28
4x + 4y = 24. equation 1
5x + 4y = 28. equation 2
Now we can subtract the second equation by the first equation and isolate one variable:
equation 2 - equation 1
5x - 4x + 4y - 4y = 28 - 24
x = 4
Now that we discovered our x value ( How many people ordered chicken salad ) , we can apply it to one of the equations and discover y ( how many people ordered egg salad)
x + y = 6
x= 4
4 + y = 6
We can shift 4 to the other side of the equation by subtracting 4 from both sides of the equation:
4 - 4 + y = 6 - 4
y = 2
x=4 and y=2
So the awnser is :
4 people ordered chicken salad and 2 people ordered egg salad!
I hope you understood my brief explanation!!
p.s if you want to know how to use another method to solve these problems ( Substition) , just let me know in a comentary down here