Answer:
Let X the random variable that represent the delivery times of a population, and for this case we know the distribution for X is given by:
Where
and
Since the distribution of X is normal then we know that the distribution for the sample mean
is given by:
And we have;


Step-by-step explanation:
Assuming this question: The delivery times for all food orders at a fast-food restaurant during the lunch hour are normally distributed with a mean of 14.7 minutes and a standard deviation of 3.7 minutes. Let R be the mean delivery time for a random sample of 40 orders at this restaurant. Calculate the mean and standard deviation of
Round your answers to two decimal places.
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the delivery times of a population, and for this case we know the distribution for X is given by:
Where
and
Since the distribution of X is normal then we know that the distribution for the sample mean
is given by:
And we have;


Answer:



Step-by-step explanation:
Given
Let the three sides be represented with A, B, C
Let the angles be represented with 
[See Attachment for Triangle]



What the question is to calculate the third length (Side B) and the other 2 angles (
)
Solving for Side B;
When two angles of a triangle are known, the third side is calculated as thus;

Substitute:
,
; 




Take Square root of both sides



<em>(Approximated)</em>
Calculating Angle 

Substitute:
,
; 




Subtract 180 from both sides


Divide both sides by -144



Take arccos of both sides



<em>(Approximated)</em>
Calculating 
Sum of angles in a triangle = 180
Hence;



Make
the subject of formula


Answer:
Step-by-step explanation:
Alright so we are going to solve
5x ≥ 25 Divide both sides by 5
x≥5
Answer:heyyy there...the answer is b that is -12x^3+12x^2-20
Step-by-step explanation:
<h3>f(x)=
-12x^3+19x^2-5</h3><h3>g(x)=
7x^2+15</h3><h3>f(x)-g(x)=(
-12x^3+19x^2-5)-( 7x^2+15)...{while opening the bracket the sign of the second polynomial changes accordingly}</h3><h3>
it becomes -12x^3+19x^2-5-7x^2-15</h3><h3>
=-12x^3+12x^2-20</h3><h3>
HOPE IT HELPED UUUU</h3>