Answer:
And we can find this probability with this difference:
And in order to find these probabilities we can use tables for the normal standard distribution, excel or a calculator.
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 costs of services of a population, and for this case we know the distribution for X is given by:
Where
and
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability with this difference:
And in order to find these probabilities we can use tables for the normal standard distribution, excel or a calculator.
Answer:
12x ≤ 100
Step-by-step explanation:
12*( x amount of washes) is less than or equal to 100$
Answer:
4293 4743838 44u4u3
Step-by-step explanation:
Complete question :
Different dealers may sell the same car for different prices. The sale prices for a particular car are normally distributed with a mean and standard deviation of 26 thousand dollars and 2 thousand dollars, respectively. Suppose we select one of these cars at random. Let X represent the sale price (in thousands of dollars) for the selected car.1. Find P(26< X<30) You may round your answer to two decimal places
Answer:
0.48
Step-by-step explanation:
Mean, m = 26000 ; Standard deviation, s = 2000
P(x < x)
Zscore = (x - m) / s
P(26< X<30) ;
P[(26 - 26 / 2) < (30 - 26) / 2)]
P[(0 < Z < 2)]
P(Z < 2) - P(Z <0)
Using a z table of z calculator, we can obtain the probabilties of the Z value :
0.97725 - 0.5
= 0.47725
= 0.48 ( 2 decimal places)