Answer:
Hence, the probability that seven or more of them used their phones for guidance on purchasing decisions is 0.7887
Step-by-step explanation:
We are given the following information in the question:
We treat people using phones in the store for guidance as a success.
P(People use phone for guidance) = 57% = 0.57
Then the number of people follows a binomial distribution, where
Formula:

where n is the total number of observations, x is the number of success, p is the probability of success.
Now, we are given n = 14 and x = 7
We have to evaluate:

Hence, the probability that seven or more of them used their phones for guidance on purchasing decisions is 0.7887
Answer:
a) Mean, E(X) = - 0.5
Variance = = 9.25
b) 
or
⇒ 
⇒ 
Step-by-step explanation:
Given:
moment generating function of X as:
MX(t) = 
a) Now
Mean, E(X) =
Thus,

or

also,
Thus,

or

Therefore,
Mean, E(X) = 
or
Mean, E(X) = - 0.5
and

or
= 9.5
also,
Variance(X) = E(X²) - E(X)²
⇒ 9.5 - (-0.5)²
= 9.25
b) Now,
Let f(x) be the PMF of X
Thus,

or
⇒ 
⇒ 
Therefore,
at x = 0, P(x) =
at x= - 4 ,P(x) = 
at x = 5, P(x) =
Thus,
E(X) =
or
E(X) = - 0.5
also,
= 9.5
Hence,
Var(X) = E(X²) - E(X)²
⇒ 9.5 - (-0.5)²
= 9.25
Answer:
You were close; you don’t have to add 3x to the right side though.
We’re given 2y= -3x + 6
Step one: divide both sides by 2
y= (-3/2)x + 3
Answer:
1500
Step-by-step explanation:
Hope this helps~ :D