Answer:
Step-by-step explanation:1math problem in 30seconds
We are given the following data:
Sample Size = n = 1000
Sample Mean = u = 15 hours
Population Standard Deviation = s = 2 hours
Since we know the population standard deviation, we can use z distribution to find the confidence interval about the mean. z value for 95% confidence interval is 1.96.
Formula for the confidence interval is:

Using the values in the formula, we get:

Therefore, the 95% confidence interval about the population mean is 14.88 hours to 15.12 hours. So B option is the correct answer.
Answer:
15 x 1 + 5 x 3 = 30
Step-by-step explanation:
If you turn the x into a one then it multiplies 15 by one and then it remains at 15, then you multiply 5 and 3 so that's 15 and then 15 + 15 is 30.
B) 17/6
First I multiply 2 times 6 which gave me 12 then I added 12 plus 5 which gave me 17 then I used the number at the bottom which is 6 so the final answer was 17/6
30 percentage decrease, if you need me to explain I’ll be glad to help