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:
The correct choices are; B,C,E, and F.
Step-by-step explanation:
The given equation is;

We solve for m to obtain:

We also solve the remaining equations to see which ones give the same result.
A: 
B:
C:
D: 

E: 

F: 

The equivalent equations are; B,C,E, and F.
Hi there! The third option shows us the best setup.
We can find the area of a triangle with the standard formula area = 1/2 * base * height.
To be able to fill in this formula, we need to have a base and a height. We can't easily find a triangle with given base and height, so we must look for another option.
We can also take the area of a square (length × width) and then divide the answer by 2. This is possible when we take the third setup. Hence the third answer is correct.
Answer:
∠ 1 = 120°
Step-by-step explanation:
Note that ∠ Q and ∠ R are congruent, that is both 30°, thus
∠ 1 = 180° - (30 + 30)° = 180° - 60° = 120°