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;


Answers:
B: <em>The sine function increases on (0°, 90°) and (270°, 360°).</em>
C: <em>The cosine function decreases on (0°, 180°).</em>
E: <em>Both the cosine and sine functions have a maximum value of 1.</em>
F: <em>Both the cosine and sine functions are periodic.</em>
Answer:
we conclude that Kiera got the right 63 questions.
Step-by-step explanation:
Total questions = 90
The percentage of correct question = 70%
Using the formula
The number of correct questions = 70% of 90
= [70/100] × 90
= 0.7 × 90
= 63
Therefore, we conclude that Kiera got the right 63 questions.
Answer:
3)x=-9
4)x=-2
5)x=-4
6)x=-5
7)x=-12
8)x=-11
Step-by-step explanation:
My opinion about this answer is 7