The two pieces are continuous for every
So, our only concern is to make sure that the pieces "glue" continuously at x=7.
To ensure this, we evaluate both pieces at x=7, and impose that the two values are equal.
The first piece evaluates to
The second piece evaluates to
So, we want
We move all terms involving c to the left hand side, and all the numerical constants on the right hand side:
Answer:
The margin of error for a confidence interval for the population mean with a 90% confidence level is 0.53 hours.
Step-by-step explanation:
We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of .
So it is z with a pvalue of , so
Now, find the margin of error M as such
In which is the standard deviation of the population and n is the size of the sample.
In this quesstion:
So
The margin of error for a confidence interval for the population mean with a 90% confidence level is 0.53 hours.