Answer:
răspuns corect :a 2x -8y +3
Step-by-step explanation:
dami coroana te rog
Answer:
We need a sample size of at least 75.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so 
Now, we find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.
The standard deviation is the square root of the variance. So:

With a .95 probability, the sample size that needs to be taken if the desired margin of error is 5 or less is
We need a sample size of at least n, in which n is found when M = 5. So







We need a sample size of at least 75.
With pythagorean theorem and working backwards, you do 8100-1225 to get 6875, you then get the square root of that to get x=82.91 or rounded to 82.92
Answer:
In economics, a portfolio is a term for a specific set of stocks, bonds, shares, and other securities owned by an investor. In general, the investor seeks to compile and diversify a portfolio of securities that offers maximum profitability and at the same time is diverse, in order to minimize possible risks. In general, these types of portfolios are considered efficient, as they do not leave the investment risk tied to a single factor. However, these two goals often go against each other, so the composition of the portfolio means a certain compromise.
9514 1404 393
Answer:
16) No
17) (c)
Step-by-step explanation:
For a lot of multiple-choice matrix problems, a simple test is all that is needed to determine the correct answer.
16) The determinant of A is (-2)(-2) -(2)(-3) = 10. So, we expect to see values in the inverse matrix that are 0.2 and 0.3. Alas, they're not there. The matrices are not inverses.
A^-1 = [[-.2, .3][-.2, -.2]]
__
17) The matrices are both 3×3, so their product is possible (eliminates choice D). The upper left term is different among the answer choices, so we can determine the correct one by computing that term only.
BA=C
c11 = (5)(1) +(7)(5) +(3)(-1) = 5 +35 -3 = 37
This matches the third choice (C).
If you use a calculator to compute the full matrix product, it matches choice C in all details.