Answer:
The probability that a randomly selected call time will be less than 30 seconds is 0.7443.
Step-by-step explanation:
We are given that the caller times at a customer service center has an exponential distribution with an average of 22 seconds.
Let X = caller times at a customer service center
The probability distribution (pdf) of the exponential distribution is given by;
Here, 
= exponential parameter
Now, the mean of the exponential distribution is given by;
Mean = 
So, 
⇒ 
SO, X ~ Exp()
To find the given probability we will use cumulative distribution function (cdf) of the exponential distribution, i.e;
; x > 0
Now, the probability that a randomly selected call time will be less than 30 seconds is given by = P(X < 30 seconds)
P(X < 30) = 
= 1 - 0.2557
= 0.7443
Answer:
The answer is C i.e y = 3.25 x + 4.60
Step-by-step explanation:
Given the graph in which the Javier made a scatter plot to show the data he collected on the growth of a plant.
Now, we have to choose the equation which best represents Javier's data.
The graph shown does not pass through origin therefore intercept can not be equal to 0. hence solution A discarded.
The graph of rest of three solutions attached and the points which shown in the graph match to the points on the graph of solution third as shown. Hence, The answer is C i.e y = 3.25 x + 4.60
Given that:
Consider it is 
instead of 10 on two places.
is between 3 and 4. So, Beau thinks a good estimate for is = 3.5.
Solution:
To find , Beau found 3² = 9 and 4² = 16.
He said that since 10 is between 9 and 16.
Since 10 is close to 9, therefore must be close to 3. So, Beau's estimate is high.
Now,
Since, 10 lies between 9.61 and 10.24, therefore must be lies between 3.1 and 3.2.
Therefore, the estimated value of is 3.15.
The numbers are being multiplied by 7
.5 • 7 = 3.5
3.5 • 7 = 24.5
24.5 • 7 = 171.5
etc
3x²-8x+4=0
(3x-2) (x-2)=0
x=2/3 , x = 2
Hence, the polynomial has two positive roots.
Option A is the correct choice.
