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
Answer:
-4n - 11
Step-by-step explanation:
Step 1: Convert words into an expression
11 less than the product of a number and -4
(n * -4) - 11
<em>-4n - 11</em>
<em />
Answer: -4n - 11
<u>If needed solve</u>
-4n - 11 + 11 = 0 + 11
-4n / -4 = 11 / -4
<em>n = -2.75</em>
Answer:
7 miles per hour
Step-by-step explanation:
3 1/2 miles = 7/2 miles
1/2 hours= 30 minutes
So,
In 30 mins, travelled 7/2 miles
In 1 min, travelled 7/2 ÷ 30= 7/2× 1/30 = (7×1)/(2×30) = 7/60 miles
In 60 mins, travelled (7×60)/60 miles = 420/60 miles = 7 miles.
Hence, the speed is 7 miles per hour.
Hope this helps :)
7 is 35% of x.
Thus, since 35% = 35/100,
35% of x is 7, so 35/100 * x = 7.
35x/100 = 7
35x=700
x = 20
7 is 35% of 20.