She has 12 necklaces in 2 hours. How long will it take her to make 9 necklaces
2 answers:
You might be interested in
Answer:
To drain the water tower it will take 36 hours.
Step-by-step explanation:
Given:
A 72,000 water tower is being drained, and in an hour 2000 gallons are drained.
Now, to calculate the hours it would take to drain total 72,000 gallons of water, we should divide the gallons of water drained in one hour by total gallons of water in the tower.
Gallons of total water in the tower ÷ Gallons of water drained per hour
Therefore, to drain the water tower it will take 36 hours.
Answer:
The upper limit of a 95% confidence interval for the population mean would equal 83.805.
Step-by-step explanation:
The standard deviation is the square root of the variance. Since the variance is 25, the sample's standard deviation is 5.
We have the sample standard deviation, not the population, so we use the t-distribution to solve this question.
T interval:
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 15 - 1 = 14
Now, we have to find a value of T, which is found looking at the t table, with 14 degrees of freedom(y-axis) and a confidence level of 0.95(). So we have T = 1.761
The margin of error is:
M = T*s = 1.761*5 = 8.805.
The upper end of the interval is the sample mean added to M. So it is 75 + 8.805 = 83.805.
The upper limit of a 95% confidence interval for the population mean would equal 83.805.