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
Answer:I do not speak
Step-by-step explanation: if u answer them all you get I do not speak I hope this helped :)
A would be 1 as b would be -4
Answer:yes
Step-by-step explanation:
Answer:
C. 303,000 Joules
Step-by-step explanation:
1. use abcos(theta)
a=50
b=7000
theta=30 degrees
2. (50)(7000)cos(30)=303,000