Answer:
a) 0.9
b) Mean = 1.58
Standard Deviation = 0.89
Step-by-step explanation:
We are given the following in the question:
A marketing firm is considering making up to three new hires.
Let X be the variable describing the number of hiring in the company.
Thus, x can take values 0,1 ,2 and 3.

a) P(firm will make at least one hire)

Also,


b) expected value and the standard deviation of the number of hires.
![E(x^2) = \displaystyle\sum x_i^2P(x_i)\\=0(0.1) + 1(0.4) + 4(0.32) +9(0.18) = 3.3\\V(x) = E(x^2)-[E(x)]^2 = 3.3-(1.58)^2 = 0.80\\\text{Standard Deviation} = \sqrt{V(x)} = \sqrt{0.8036} = 0.89](https://tex.z-dn.net/?f=E%28x%5E2%29%20%3D%20%5Cdisplaystyle%5Csum%20x_i%5E2P%28x_i%29%5C%5C%3D0%280.1%29%20%2B%201%280.4%29%20%2B%204%280.32%29%20%2B9%280.18%29%20%3D%203.3%5C%5CV%28x%29%20%3D%20E%28x%5E2%29-%5BE%28x%29%5D%5E2%20%3D%203.3-%281.58%29%5E2%20%3D%200.80%5C%5C%5Ctext%7BStandard%20Deviation%7D%20%3D%20%5Csqrt%7BV%28x%29%7D%20%3D%20%5Csqrt%7B0.8036%7D%20%3D%200.89)
Answer:
Which cost category in the table shows an example of direct variation? WEED-HAND
The total cost for office expenses to run the organic strawberry farm varies directly with the number of months it is used. Which equation represents this scenario? Y=63x
What would be the cost for office expenses for 24 months? $1512.00
Step-by-step explanation:
Answer:
20.33%
Step-by-step explanation:
We have that the mean (m) is equal to 87.5, the standard deviation (sd) 6.25 and the sample size (n) = 12
They ask us for P (x <86)
For this, the first thing is to calculate z, which is given by the following equation:
z = (x - m) / (sd / (n ^ 1/2))
We have all these values, replacing we have:
z = (86 - 87.5) / (6.25 / (12 ^ 1/2))
z = -0.83
With the normal distribution table (attached), we have that at that value, the probability is:
P (z <-0.83) = 0.2033
The probability is 20.33%