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:
Solve for the first variable in one of the equations, then substitute the result into the other equation.
Point Form:
(−1/2,1/2)
Equation Form:
x=−1/2,y=1/2
Step-by-step explanation:
Who is my work I think the answer would be -190
Answer:
what is the full question?
Step-by-step explanation:
Option A) 14/250 = N/350 is correct.
Kevin wants to change the engine in her car. The current engine is 250 cubic centimeters and has a 14 inch fan belt. The new engine is 350 cubic centimeters and has proportionally larger fan belt.
<h3>What is proportionality?</h3>
proportionality can be defined as, how much the number is relatable to other number i.e. x =2y x is two times proportion to y.
Hence, in the question
for 250 cc engine it has 14 inch belt
for 350 cc engine it has N inch belt(let)
proportionality can be given as
14 ∝ 250
N ∝ 350
dividing both equation
N/14=350/250
or 14/250=N/350
Thus, the required proportion is given as 14/250=N/350.
Learn more about proportionality here:
brainly.com/question/8598338
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