A cyclist rides 24 miles at an average speed of 9 miles per hour. At what rate must the cyclist cover the next 20 miles in order
1 answer:
You might be interested in
Answer:
1) x= -36.
2) x = 0.
Step-by-step explanation:
1) Taking the 3rd power to both sides and using the following exponent law:
we get:
So this tells us that x = -36.
2) We can distribute the power inside every term. So the left side becomes:
Now, the trick here is to remember that , so replacing 1 with
, which then gives us:
, telling us that 3x = 0 and thus, x = 0.
Answer:
So on this case the 95% confidence interval would be given by (315839.52;324416.48)
Step-by-step explanation:
Previous concepts
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
represent the sample mean
population mean (variable of interest)
represent the population standard deviation
n=529 represent the sample size
Solution to the problem
The confidence interval for the mean is given by the following formula:
(1)
Since the Confidence is 0.95 or 95%, the value of and
, and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.025,0,1)".And we see that
Now we have everything in order to replace into formula (1):
So on this case the 95% confidence interval would be given by (315839.52;324416.48)