Answer:
3x - y = -1
Step-by-step explanation:
Standard form of equation is Ax + By = C
y - y1 = m (x -x1)
y - 7 = 3 (x - 2)
y - 7 = 3x - 6
3x - y = -7 +6
3x - y = -1
Distance of 10 blocks
Displacement of 2 blocks north
Answer: 80%
Explanation:
From the provided graph, read the Relative Cumulative Frequency as 0.8 (or 80%) which corresponds to a GPA of 3.5.
This number represents all GPAs lower than 3.5.
Answer:
a. CI=[128.79,146.41]
b. CI=[122.81,152.39]
c. As the confidence level increases, the interval becomes wider.
Step-by-step explanation:
a. -Given the sample mean is 137.6 and the standard deviation is 20.60.
-The confidence intervals can be constructed using the formula;

where:
is the sample standard deviation
is the s value of the desired confidence interval
we then calculate our confidence interval as:
![\bar X\pm z\frac{s}{\sqrt{n}}\\\\=137.60\pm z_{0.05/2}\times\frac{20.60}{\sqrt{21}}\\\\=137.60\pm1.960\times \frac{20.60}{\sqrt{21}}\\\\=137.60\pm8.8108\\\\\\=[128.789,146.411]](https://tex.z-dn.net/?f=%5Cbar%20X%5Cpm%20z%5Cfrac%7Bs%7D%7B%5Csqrt%7Bn%7D%7D%5C%5C%5C%5C%3D137.60%5Cpm%20z_%7B0.05%2F2%7D%5Ctimes%5Cfrac%7B20.60%7D%7B%5Csqrt%7B21%7D%7D%5C%5C%5C%5C%3D137.60%5Cpm1.960%5Ctimes%20%5Cfrac%7B20.60%7D%7B%5Csqrt%7B21%7D%7D%5C%5C%5C%5C%3D137.60%5Cpm8.8108%5C%5C%5C%5C%5C%5C%3D%5B128.789%2C146.411%5D)
Hence, the 95% confidence interval is between 128.79 and 146.41
b. -Given the sample mean is 137.6 and the standard deviation is 20.60.
-The confidence intervals can be constructed using the formula in a above;
![\bar X\pm z\frac{s}{\sqrt{n}}\\\\=137.60\pm z_{0.01/2}\times\frac{20.60}{\sqrt{21}}\\\\=137.60\pm3.291\times \frac{20.60}{\sqrt{21}}\\\\=137.60\pm 14.7940\\\\\\=[122.806,152.394]](https://tex.z-dn.net/?f=%5Cbar%20X%5Cpm%20z%5Cfrac%7Bs%7D%7B%5Csqrt%7Bn%7D%7D%5C%5C%5C%5C%3D137.60%5Cpm%20z_%7B0.01%2F2%7D%5Ctimes%5Cfrac%7B20.60%7D%7B%5Csqrt%7B21%7D%7D%5C%5C%5C%5C%3D137.60%5Cpm3.291%5Ctimes%20%5Cfrac%7B20.60%7D%7B%5Csqrt%7B21%7D%7D%5C%5C%5C%5C%3D137.60%5Cpm%2014.7940%5C%5C%5C%5C%5C%5C%3D%5B122.806%2C152.394%5D)
Hence, the variable's 99% confidence interval is between 122.81 and 152.39
c. -Increasing the confidence has an increasing effect on the margin of error.
-Since, the sample size is particularly small, a wider confidence interval is necessary to increase the margin of error.
-The 99% Confidence interval is the most appropriate to use in such a case.
Answer:
The decision rule is
Fail to reject the null hypothesis
The conclusion is
There is no sufficient evidence to conclude that older people are slower
Step-by-step explanation:
From the question we are told that
The average time taken is
The sample size is
The sample mean is 
The standard deviation is 
The null hypothesis is
The alternative hypothesis is
Generally the test statistics is mathematically represented as

=>
=> 
From the z table the area under the normal curve to the right corresponding to 0.7825 is

So from the question we see that the
hence
The decision rule is
Fail to reject the null hypothesis
The conclusion is
There is no sufficient evidence to conclude that older people are slower