Answer:
Rational
Step-by-step explanation:
√4 asks "what times itself is 4?"
The answer is 2.
2x2=4
√4 = 2
2 is rational.
Answer:
the greatest common factor is 2, so the expression could be rewritten 
Step-by-step explanation:
we can factor out z
so that'll be
z((1/m)-(1/n))=1
divide by the value in parentheses on both sides
z=1/((1/m)-(1/n))
I can't tell if there's more the problem wants you to do. I could rewrite the equation on paper more easily, but I don't have one on hand
Answer:
0.36427
Step-by-step explanation:
Mean = λ = 18 messages per hour
P(X = x) = (e^-λ)(λ⁻ˣ)/x!
P(X ≤ x) = Σ (e^-λ)(λ⁻ˣ)/x! (Summation From 0 to x)
But the probability required is that the messages thay come in an hour is between 15 and 20, that is, P(15 < X < 20)
P(15 < X < 20) = P(X < 20) - P(X ≤ 15)
These probabilities will be evaluated using a cumulative frequency calculator.
P(X < 20) = 0.65092
P(X ≤ 15) = poissoncdf(18, 15) = 0.28665
P(15 < X < 20) = P(X < 20) - P(X ≤ 15) = 0.65092 - 0.28665 = 0.36427.
You can use the Poisson distribution calculator here
https://stattrek.com/online-calculator/poisson.aspx
