Answer:
Yes, the confidence interval contradict this statement.
Step-by-step explanation:
The complete question is attached below.
The data provided is:
Since the population standard deviations are not provided, we will use the <em>t</em>-confidence interval,
Compute the pooled standard deviation as follows:
The critical value is:
*Use a <em>t</em>-table.
The 95% confidence interval is:
The 95% confidence interval for the difference between the mean weights is (0.43, 1.37).
To test the magazine's claim the hypothesis can be defined as follows:
<em>H</em>₀: There is no difference between the mean weight of 1-year old boys and girls, i.e. .
<em>H</em>ₐ: There is a significant difference between the mean weight of 1-year old boys and girls, i.e. .
Decision rule:
If the confidence interval does not consists of the null value, i.e. 0, the null hypothesis will be rejected.
The 95% confidence interval for the difference between the mean weights does not consists the value 0.
Thus, the null hypothesis will be rejected.
Conclusion:
There is a significant difference between the mean weight of 1-year old boys and 1-year old girls.
