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:
b, c, d, e
Step-by-step explanation:
a) 18/24 = 75%
b) 18/20 = 90%
c) 36/40 = 90%
d) 54/60 = 90%
e) 81/90 = 90%
It would be 3^x=14 and you just have to find out what number raised to 3 equals 14
Answer:
3 times
Step-by-step explanation:
Firstly we calculate the number of minutes between 8 and 11 am
The number of hours is 3 hours
The number of minutes is 180 minutes since 1 hour is 60 minutes
Now out of 180, to know the number of times that they both leave, we need to get the multiples of both between 0 and 180
The multiples are;
60, 120, 180
This means that they leave together 3 times
