A recent national study about the effectiveness of Echinacea in cold treatments for adults was performed by a medical school in Kansas City. The results stated that 22.5% of the randomly chosen 250 adult subjects in the placebo group in the study noted that their treatment appeared to shorten the length of their colds. In an attempt to determine the average high school GPA of all students enrolled at a Regents University in Kansas, a researcher first randomly selects one of the six Regents Universities, then selects a random sample of 50 students from that University from which to gather data. The descriptive statistic of interest in this study is

The average high school GPA of all students enrolled at a Regents University in Kansas

Step-by-step explanation:

Descriptive statistics refers to aspect of statistics which is employed when summarizing data. Descriptive statistics often use measure of center such as, mean, median and mode to give consider summary of both sample and population data. Measures of spread such as standard deviation and variance and so on also form part of descriptive statistics used for data summarization.

In the scenario described above, the descriptive statistic which the study intends to infer is the average or mean high school GPA of all students enrolled at a Regents University in Kansas. This mean value will be a single value which describes the GPA of all high school students.

hello from mrbilldoesmath!

answer:

x - 3

discussion:

x^2 - 9 = (x-3) (x+3)   so

(x^2-9)/ (x + 3) = x-3

you,

mrb

answer is x<