Answer:
A. E(x) = 1/n×n(n+1)/2
B. E(x²) = 1/n
Step-by-step explanation:
The n candidates for a job have been ranked 1,2,3....n. Let x be the rank of a randomly selected candidate. Therefore, the PMF of X is given as
P(x) = {1/n, x = 1,2...n}
Therefore,
Expectation of X
E(x) = summation {xP(×)}
= summation {X×1/n}
= 1/n summation{x}
= 1/n×n(n+1)/2
= n+1/2
Thus, E(x) = 1/n×n(n+1)/2
Value of E(x²)
E(x²) = summation {x²P(×)}
= summation{x²×1/n}
= 1/n
3/5 is smaller. if you look at the ruler 3/5 will be first and then 3/8th
Answer:
x = -11/5 and y = 24/5
Step-by-step explanation:
Use elimination.
First, we need to multiply so that at least one variable can cancel out.
We can multiply the top equation by 2.
So we get
4x + 6y = 20
Then, we can use elimination.
The x's cancel out.
So we get 5y = 24
Or y = 24/5
Then, we can plug in this y value back into the first equation to find x.
2x + 3(24/5) = 10
2x + 72/5 = 50/5
2x = -22/5
x = -11/5
So x = -11/5 and y = 24/5
Answer:
X should equal 65, sorry if I’m wrong
Step-by-step explanation: