Calculate the value of z and its probability, since with this we can know how likely it is that this will happen.
We have that the mean (m) is equal to 8.3, the standard deviation (sd) 1.2 and the sample size (n) = 15
They ask us for P (x =7.2)
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 = (7.2 - 8.3) / (1.2 / (15 ^ (1/2))
z = -3.55
With the normal distribution table (attached), we have that at that value the approximate probability is:
P (z = -3.55) = 0.0001
The probability is 0.01 %
This affirms that the students do not sleep what the study says because the probability of this happening according to the survey is almost nil.
Answer:
Equation for cost of the hall restoration fee 70.4 + 52.8 + 11f = 128 .15 and the cost of the hall restoration fee is $0.45 .
Step-by-step explanation:
Let us assume that the hall restoration fee be f .
As given
The ticket price for a concert at a historic music hall includes.
$6.40 for the concert $4.80 for the program and a hall restoration fee the price for 11 tickets is$128.15 .
Than the equation becomes
(Cost for concert + Cost for program + Hall restoration fee) × Number of tickets = Total amount of 11 tickets
Putting all the values in the above
(6.40 + 4.80 + f) × 11 = 128.15
Open the bracket
6.40 × 11 + 4.80 × 11 + 11f = 128.15
70.4 + 52.8 + 11f = 128 .15
11f = 128 .15 - 123.2
11f = 4.95

f = $ 0.45
Therefore the equation for cost of the hall restoration fee 70.4 + 52.8 + 11f = 128 .15 and the cost of the hall restoration fee is $0.45 .
Answer:
Step-by-step explanation:
x2-9 = 0
Area of one dimension = x-3= 0
So, x2= 9
Square root on both sides;
x= +3 and -3
x-3 is one side
x+3 is the other dimension
Answer:
no they are not because 11, 14 is the only one that has a vertices
Step-by-step explanation: