Answer:
And the interval would be:
Step-by-step explanation:
For this problem we have the following dataset given:
44 32.8 59.2 31.4 12.7 68.5 84.7 72.5 55.7
We can find the mean and sample deviation with the following formulas:
And replacing we got:
The confidence interval for the mean is given by:
The degrees of freedom are:
The confidence would be 0.98 and the significance then the critical value would be:
Ad replacing we got:
And the interval would be: