Complete Question
The complete question is shown on the uploaded image
Answer:
1 ) The correct option B
2) The correct option is C
3) The correct option is C
4) The correct option is C
Step-by-step explanation:
From the question we are told that
The proportion that own a cell phone is 
The sample size is n = 15
Generally the appropriate distribution for X is mathematically represented as

So

Generally the number students that own a cell phone in a simple random sample of 15 students is mathematically represented as



Generally the standard deviation of the number of students who own a cell phone in a simple random sample of 15 students is mathematically represented as

Where q is mathematically evaluated as





Generally the probability that all students in a simple random sample of 15 students own a cell phone is mathematically represented as

From the combination calculator is 


Answer:
Step-by-step explanation:
Hello!
The variable of interest in this case is:
X: length of time before a major repair is required on a new car. (months)
This variable has a normal distribution with mean μ= 36 months and a standard deviation σ= 9 months.
If he wants to set a guarantee period in which only 5% of the sold cars fell, the objective is to find the value of X that has below 5% of the cars that need major repairs before the end of the guarantee period.
Check the attachment, the curve represents the distribution of the population of the time it takes before a new car needs major repairs, I've marked approximately where this value of X should be.
Symbolically:
P(X≤a)=0.05
To reach the proper value of "a" you have to work using the standard normal distribution because is a tabulated distribution and you can extrapolate it to any normal distribution.

So the first step is to look in the table of the Z distribution for the value that accumulates 0.05 of probability since it is such a low probability, you have to look for the value in the left side of the table (negative values of Z). You look for 0.05 in the body of the table and then the margins for the corresponding value (see second attachment)

Then the value that accumulates 0.05 of probability is -1.64, now you have to reverse the standardization to reach the asked value of X
Z= (a- μ)/σ
(Z*σ)= a - μ
a=(Z*σ)+ μ
a=(-1.64*9)+36
a= 21.24 months.
The guarantee period should be 21.24 months so that only 5% of the sold cars will need major repairs before it wears of.
I hope it helps!
Speak in English please. I would be more pleased to help if you write in English.
To solve this problem we want to let X equal the amount of points that team A scored. Now we want to express the amount of points that team B scored in terms of X. If team A scored 7 more points than team B then team B scored X-7 points. We know that together they scored 163 points so we can set up this equation: x + x - 7 = 163 2x - 7 = 163 2x = 155 X = 78 Team A scored 78 points
The radian is with a denominator of 5 is 2.5