Answer:
The given system has NO SOLUTION.
Step-by-step explanation:
Here, the given system of equation is:
6 x - 2 y = 5 .......... (1)
3 x - y = 10 .... (2)
Multiply equation 2 with (-2), we get:
3 x - y = 10 ( x -2)
⇒ - 6 x + 2 y = - 20
Now, ADD this to equation (1) , we get:
6 x - 2 y - 6 x + 2 y = 5 - 20
or, 0 = - 15
WHICH IS NOT POSSIBLE as 0 ≠ -15
Hence, the given system has NO SOLUTION.
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: 10.50 is what she has left to spend
Step-by-step explanation: Hope it helps!