The coefficients of x and y in the first equation are 3 and -4, respectively.
The coefficients of x and y in the second equation are 1 and 6, respectively.
The coefficient matrix lists these coefficients in order on successive rows, so it will be ...
![\left[\begin{array}{cc}3&-4\\1&6\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D3%26-4%5C%5C1%266%5Cend%7Barray%7D%5Cright%5D)
36 because 6 to the second power is 36
Answer:
27% of the possible Z values are greater than 0.613
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:

27% of the possible Z values are greater than
The 100 - 27 = 73rd percentile, which is X when Z has a pvalue of 0.73. So X when the z-score is 0.613.



27% of the possible Z values are greater than 0.613
Answer:


Then we can find the probability of interest with this difference:
And using the normal standard distribution or excel we got:
So then the probability that the sample mean would differ from the true mean by less than 28 dollars from the sample of 55 is approximately 0.390
Step-by-step explanation:
We define the variable of interest as the per capita income and we know the following properties for this variable:
and
We want to find this probability:
We select a sample size of n=55 and we define the z score formula given by:

We can find the z score then for 20880 and 20936 and we got:


Then we can find the probability of interest with this difference:
And using the normal standard distribution or excel we got:
So then the probability that the sample mean would differ from the true mean by less than 28 dollars from the sample of 55 is approximately 0.390