Answer:
Step-by-step explanation:
Since the population standard deviation 
is unknown, and the sample standard deviation 
, must replace it, the 
distribution must be used for the confidence interval.
The sample size is n=8.
The degree of freedom is 
, 
.
With 95% confidence level, the 
(significance level) is 5%.
Hence with 7 degrees of freedom, 
. (Read from the t-distribution table see attachment)
The 95% confidence interval can be found by using the formula:
.
The sample mean is 
hours.
The sample sample standard deviation is 
hours.
We now substitute all these values into the formula to obtain:
.
We are 95% confident that the population mean is between 26.12 and 31.48 hours.
Answer:
Step-by-step explanation:
103x.87=89.61
103+89.61=192.61
Answer:
53
Step-by-step explanation:
42/6=7
7*5=35
18+35=53
Answer:
300 cupcakes
Step-by-step explanation:
Answer:
Step-by-step explanation:
Add up all the values for the height and divide by 9. do the same for the leaf scars.
