Answer:
Prime
Step-by-step explanation:
x² + 20x − 36
You must find a pair of numbers that multiply to give -36 and add to give +20.
The likely candidates are 2 and 18, and they must have opposite signs to give a negative product.
+2 × (-18) = -36; +2 + (-18) = -16
-2 × 18 = -36; -2 + 8 = +16
Neither combination gives +20 as the sum.
The expression can't be factored with rational numbers.
The expression is prime.
Answer:
a) 
b) 
And replacing we got:
![P(X \geq 3) = 1- [0.2+0.3+0.1]= 0.4](https://tex.z-dn.net/?f=%20P%28X%20%5Cgeq%203%29%20%3D%201-%20%5B0.2%2B0.3%2B0.1%5D%3D%200.4)
c) 
d) 
e) 
f) 
And replacing we got:

And the variance would be:
![Var(X0 =E(X^2)- [E(X)]^2 = 6.4 -(2^2)= 2.4](https://tex.z-dn.net/?f=%20Var%28X0%20%3DE%28X%5E2%29-%20%5BE%28X%29%5D%5E2%20%3D%206.4%20-%282%5E2%29%3D%202.4)
And the deviation:

Step-by-step explanation:
We have the following distribution
x 0 1 2 3 4
P(x) 0.2 0.3 0.1 0.1 0.3
Part a
For this case:

Part b
We want this probability:

And replacing we got:
![P(X \geq 3) = 1- [0.2+0.3+0.1]= 0.4](https://tex.z-dn.net/?f=%20P%28X%20%5Cgeq%203%29%20%3D%201-%20%5B0.2%2B0.3%2B0.1%5D%3D%200.4)
Part c
For this case we want this probability:

Part d

Part e
We can find the mean with this formula:

And replacing we got:

Part f
We can find the second moment with this formula

And replacing we got:

And the variance would be:
![Var(X0 =E(X^2)- [E(X)]^2 = 6.4 -(2^2)= 2.4](https://tex.z-dn.net/?f=%20Var%28X0%20%3DE%28X%5E2%29-%20%5BE%28X%29%5D%5E2%20%3D%206.4%20-%282%5E2%29%3D%202.4)
And the deviation:

Answer:Pois(ln(200))
Step-byy-step explanation:
Let N be the number of received calls in a day
That is
N∼Pois(λ).
0.5% = 0.5/100 = 1/200 of no calls
P(N=0)=e^−λ=1/200
-λ=e^(1/200)
λ=in(200)
Our number of calls in a day is distributed Pois(ln(200)).
Answer:
fghjk
Step-by-step explanation: