The margin of error of a given statistic is an amount that is allowed for in case of miscalculation or change of circumstances.
It is usually the radius or half of the width of the confidence interval of that statistic.
Given that a<span>
survey of the students in Lance’s school found that 58% of the
respondents want the school year lengthened, while 42% think it should
remain the same. The margin of error of the survey is ±10%.
This means that 58% </span><span>± 10% of the </span>respondents want the school year lengthened, while 42% <span><span>± 10% think it should
remain the same.</span>
Thus, from 48% to 68% </span><span><span>of the respondents want the school year lengthened, while from 32% to 52% <span>think it should
remain the same.</span> </span>
Therefore, according to
the survey data, at least 32% of students want the duration of the school
year to remain unchanged, and at least 48% want the school year to be
lengthened.</span>
Answer:
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Let X the random variable that represent interest on this case, and for this case we know the distribution for X is given by:
And let 
represent the sample mean, the distribution for the sample mean is given by:
On this case 
Solution to the problem
We want this probability:
The best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
Answer: Juan walks 246,176 yards around the circular path.
To find the distance around the circular path, we are looking for the circumference. The formula for the circumference is: C = pi(r^2).
Simply plug in the radius and evaluate the expression.
C = 3.14(280^2)
C = 3.14(78400)
C = 246,176 yd
