We add up all those numbers (excluding 30) and divide by the number of numbers (9). This results in 78.8 (round up to 79).
79-74 = 5. So the mean has increased by 5 points. (C)
3 - 13x - 7x^2 - (5x^2 + 12x - 10)
Distributing the negative over the parentheses chamges the signs:-
= 3 - 13x - 7x^2 - 5x^2 - 12x + 10
adding like terms:-
= -12x^2 - 25x + 13 (answer).
Its B
Part 1:
A. = 8 • 10^20
B. = -8 • 10^20
C. = 4 • 10^25
D. = 6.25 • 10^23
A. has the greatest value
Part 2:
A. = 8 • 10^20
B. = -8 • 10^20
C. = 4 • 10^25
D. = 6.25 • 10^23
B. has the least value
Answer:
The power of the test is 0.67.
Step-by-step explanation:
The complete question is:
A researcher is evaluating the influence of a treatment using a sample selected from a normally distributed population with a mean of μ = 80 and a standard deviation σ = 20. The researcher expects a 12-point treatment effect and plans to use a two-tailed hypothesis test with α = 0.05. Compute the power of the test if the researcher uses a sample of n = 16 individuals
.
Solution:
The information provided are:

The expected mean is:

The critical <em>z</em>-score at <em>α</em> = 0.05 for a two-tailed test is:
<em>z</em> = 1.96
*Use a <em>z-</em>table.
Compute the test statistic value as follows:

The power of statistical test is well-defined as the probability that we reject a false null hypothesis.
Power = Area to the right of the critical <em>z</em> under the assumption that H₀ is false.
Location of critical <em>z</em> (in H₀ is false distribution) = 
This is negative because the critical z score is to the left of the mean of the H₀ in false distribution.
Area above z = -0
.44.
Compute the value of P (Z > -0.44) as follows:

Thus, the power of the test is 0.67.
Answer:

Step-by-step explanation:





