Answer:
105
Step-by-step explanation:
Answer:
3. All you did was switch the numbers, so it will still equal the same :)
4. 8a and the other 8a cancel each other out, so since 8 has no variables, it ends up by itself.
Answer: (47.51, 54.49)
Step-by-step explanation:
Confidence interval for population mean is given by :-

, where n= sample size .
= population standard deviation.
= sample mean
= Two -tailed z-value for
(significance level)
As per given , we have

n= 44
Significance level for 95% confidence = 
Using z-value table ,
Two-tailed Critical z-value : 
Now, the 95% confidence interval for the true population mean textbook weight will be :-

Hence, the 95% confidence interval for the true population mean textbook weight. : (47.51, 54.49)