Answer:
x > -5
Step-by-step explanation:
number of student attend the college are 3150
Step-by-step explanation:
the student teacher ratio is 35:2
let, there are 2x teachers
according to the problem,
2x = 180
or, x = 180/2
= 90
so number of students = 35 X 90 = 3150
Answer:
Confidence Interval for the mean
Step-by-step explanation:
Confidence interval is made using the observations of a <em>sample</em> of data obtained from a population, so it is constructed in such a way, that, with a certain <em>level of confidence </em>(this is the statement mentioned in the question), that is, one could have a percentage of probability that the interval, or range around the value obtained, frequently 95%, contains the true value of a population parameter (in this case, the population mean).
It is one way to extract information from a population using a sample of it. This kind of information is what inference statistic is always looking for.
An <u>approximation</u> about how to construct this interval or range:
- Select a random sample.
- For the specific case of a <em>mean</em>, you need to calculate the mean of the <em>sample </em>(sample mean), and, if standard deviation is unknown or not mentioned, also calculate the sample standard deviation.
- With this information, and acknowledged that these values follows a standard normal distribution (a normal distribution with mean 0 and a standard deviation of 1), represented by random variable Z, one can use all this information to calculate a <em>confidence interval for the mean</em>, with a certain confidence previously choosen (for example, 95%), that the population mean must be in this interval or <em>range around this sample mean.</em>
If it is a rectangle the length would be 4cm
A=L×W
20=L×5
÷5. ÷5 divide both sides by 5
4=L and you get 4
