Answer:
We conclude that children in district are brighter, on average, than the general population.
Step-by-step explanation:
We are given the following data set:
105, 109, 115, 112, 124, 115, 103, 110, 125, 99
Formula:
where
are data points,
is the mean and n is the number of observations.
![Mean = \displaystyle\frac{\text{Sum of all observations}}{\text{Total number of observation}}](https://tex.z-dn.net/?f=Mean%20%3D%20%5Cdisplaystyle%5Cfrac%7B%5Ctext%7BSum%20of%20all%20observations%7D%7D%7B%5Ctext%7BTotal%20number%20of%20observation%7D%7D)
![Mean =\displaystyle\frac{1117}{10} = 111.7](https://tex.z-dn.net/?f=Mean%20%3D%5Cdisplaystyle%5Cfrac%7B1117%7D%7B10%7D%20%3D%20111.7)
Sum of squares of differences = 642.1
![S.D = \sqrt{\frac{642.1}{49}} = 8.44](https://tex.z-dn.net/?f=S.D%20%3D%20%5Csqrt%7B%5Cfrac%7B642.1%7D%7B49%7D%7D%20%3D%208.44)
We are given the following in the question:
Population mean, μ = 106
Sample mean,
= 111.7
Sample size, n = 10
Alpha, α = 0.05
Sample standard deviation, s = 8.44
First, we design the null and the alternate hypothesis
We use one-tailed(right) t test to perform this hypothesis.
Formula:
Putting all the values, we have
Now,
Since,
![t_{stat} > t_{critical}](https://tex.z-dn.net/?f=t_%7Bstat%7D%20%3E%20t_%7Bcritical%7D)
We fail to accept the null hypothesis and reject it. We accept the alternate hypothesis.
We conclude that children in district are brighter, on average, than the general population.