Answer:
Where and
Then we have:
With the following parameters:
Step-by-step explanation:
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 number of cars running a red light of a population, and for this case we know the distribution for X is given by:
Where and
Since the distribution for X is normal then we know that the distribution for the sample mean is given by:
With the following parameters:
2 is less than 3x be the c in three and be big once you times the x number
Answer:
c 17
Step-by-step explanation:
You make 23 a day plus 3.60 per sale
Income = 23+ 3.6 s
You want to make at least 84
84 ≤ 23+ 3.6 s
Subtract 23 from each side
84 -23 ≤ 23-23 +3.6s
61 ≤ 3.6s
Divide by 3.6 on each side
61/3.6 ≤ 3.6s/3.6
16.94444 ≤ s
You must make more than 16.94444 sales
But you cannot make part of a sale so
You must make at least 17 sales