A guidance counselor is studying test anxiety in freshman students. A random sample of 972 high school freshmen finds that 219 o
f these students have had some form of test anxiety. A 95% confidence interval for the proportion of freshmen with test anxiety is (0.199, 0.252). Which statement correctly interprets the interval? The guidance counselor can be 95% confident that 23% of freshmen will have some form of test anxiety.
There is a 95% probability that the proportion of freshmen with test anxiety lies between 0.199 and 0.252.
If this procedure is repeated many, many times, the true proportion of freshmen with test anxiety will be captured 95% of the time.
The guidance counselor can be 95% confident that the interval from 0.199 to 0.252 captures the true proportion of all freshmen who have test anxiety.
D. The guidance counselor can be 95% confident that the interval from 0.199 to 0.252 captures the true proportion of all freshmen who have test anxiety.
So to set up the equation we have:
<span><span><span>4M</span><span>4+M</span></span>=<span>127</span></span>
<span>28M=12(4+M)</span>
<span>28M=48+12M</span> <span>28K−12M=48</span>
<span>(28−12)M=48</span>
<span>16K=48</span>
<span>M=<span>4816</span></span>
<span>M=3</span>
So Marna can clean the chimney alone in 3 hours
